File
saveFile
TIP
The API usage is as follows: wx.saveFile(Object object)
This API is supported by mini programs, but not by mini games.
TIP
The size limit of local file storage is 10M.
- Functional description: Save the file locally
TIP
saveFile will move the temporary file, so the tempFilePath passed in after the call is successful will not be available.
Parameters and descriptions: Object object。
Properties Type Default value Required Description tempFilePath string - Yes The temporary path of the file to be saved success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) object.success callback function parameters: Object res。
Properties Type Description savedFilePath string The file path after storage Sample code:
wx.chooseImage({
success(res) {
const tempFilePaths = res.tempFilePaths
wx.saveFile({
tempFilePath: tempFilePaths[0],
success(res) {
const savedFilePath = res.savedFilePath
}
})
}
})removeSavedFile
TIP
The API usage is as follows: wx.removeSavedFile(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Delete the local cache file.
Parameters and descriptions: Object object。
Properties Type Default value Required Description filePath string - Yes The file path to be deleted success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) Sample code:
wx.getSavedFileList({
success(res) {
if (res.fileList.length > 0) {
wx.removeSavedFile({
filePath: res.fileList[0].filePath,
complete(res) {
console.log(res)
}
})
}
}
})openDocument
TIP
The API usage is as follows: wx.openDocument(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Open a new page to open the document.
Parameters and descriptions: Object object。
Properties Type Default value Required Description filePath string - Yes File path (local path), can be obtained through downloadFile fileType string - No File type, specify the file type to open the file success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) Legal values
Value Description pdf pdf format Sample code:
wx.downloadFile({
// Example url, not real
url: 'https://example.com/somefile.pdf',
success(res) {
const filePath = res.tempFilePath
wx.openDocument({
filePath,
success(res) {
console.log('Opened document successfully')
}
})
}
})getSavedFileList
TIP
The API usage is as follows: wx.getSavedFileList(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Get the list of local cache files saved under this applet.
Parameters and descriptions: Object object。
Properties Type Default value Required Description success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) object.success callback function parameters: Object res。
Properties Type Description fileList Array.< Object>File array, each item is a FileItem The structure of res.fileList
Properties Type Description filePath string Local path size number Local file size, in bytes createTime number The timestamp when the file is saved, the number of seconds from 1970/01/01 08:00:00 to the current time Sample code:
wx.getSavedFileList({
success(res) {
console.log(res.fileList)
}
})getSavedFilelnfo
TIP
The API usage is as follows: wx.getSavedFileInfo(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Get the file information of the local file. This interface can only be used to obtain files that have been saved locally. If you need to obtain temporary file information, please use wx.getFileInfo() Interface
Parameters and descriptions: Object object。
Properties Type Default value Required Description filePath string - Yes File path success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) object.success callback function parameters: Object res。
Properties Type Description size number File size, in B createTime number The timestamp when the file is saved, the number of seconds from 1970/01/01 08:00:00 to this moment Sample code:
wx.getSavedFileList({
success(res) {
console.log(res.fileList)
}
})getFileInfo
TIP
The API usage is as follows: wx.getFileInfo(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Get the file information.
Parameters and descriptions: Object object。
Properties Type Default value Required Description filePath string - Yes Local file path digestAlgorithm string 'md5' No Algorithm for calculating file digest success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) Legal values
Value Description md5 md5 algorithm sha1 sha1 algorithm object.success callback function parameters: Object res。
Properties Type Description size number Local file size, in bytes digest string File digest calculated according to the passed digestAlgorithm Sample code:
wx.getFileInfo({
success(res) {
console.log(res.size)
console.log(res.digest)
}
})getFileSystemManager
TIP
The API usage is as follows: FileSystemManager wx.getFileSystemManager()
- Functional description: Get the globally unique file manager
- Return value: FileSystemManager File Manager.
FileSystemManager
File manager, throughwx.getFileSystemManager obtain.
.access
TIP
The API usage is as follows: FileSystemManager.access(Object object)
Functional description: Judge whether the file/directory exists
Parameters and descriptions: Object object。
Properties Type Default value Required Description path string - Yes The file/directory path to be determined whether it exists. success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) object.fail callback function parameter: Object res。
Properties Type Description errMsg string Error message Legal values
Value Description fail no such file or directory ${ path}File/directory does not exist bad file descriptor Invalid file descriptor permission denied Permission error, the file is read-only or write-only permission denied, cannot access file path The target path has no access rights (usr directory) not a directory The path specified by dirPath is not a directory, which is common when the parent path of the specified write path is a file Invalid argument Invalid parameters, you can check whether length or offset is out of bounds directory not empty The directory is not empty the maximum size of the file storage limit is exceeded Insufficient storage space, or the file size exceeds the upper limit (upper limit 100M) base64 encode error Character encoding conversion failed (for example, base64 format error) data to write is empty Written data is empty illegal operation on a directory This operation cannot be performed on a directory (for example, the specified filePath is an existing directory) file already exists ${ dirPath}There is already a file or directory with the same name value of length is out of range The length passed in is illegal value of offset is out of range The offset passed in is illegal value of position is out of range The position value is out of bounds Sample code:
const fs = wx.getFileSystemManager()
// Determine if the file/directory exists
fs.access({
path: `${wx.env.USER_DATA_PATH}/hello.txt`, success(res) {
success(res) {
// The file exists
console.log(res)
}, fail(res) { // File exists.
fail(res) {
// File does not exist or other error
console.error(res)
}
})
// Synchronization interface
try {
fs.accessSync(`${wx.env.USER_DATA_PATH}/hello.txt`)
} catch(e) {
console.error(e)
}.accessSync
TIP
The API usage is as follows: FileSystemManager.accessSync(string path)
Functional description: FileSystemManager.access The synchronous version
Parameters and descriptions: string path, The file/directory path to be determined whether it exists.
Sample code:
const fs = wx.getFileSystemManager()
// Determine if the file/directory exists
fs.access({
path: `${wx.env.USER_DATA_PATH}/hello.txt`, success(res) {
success(res) {
// The file exists
console.log(res)
}, fail(res) { // File exists.
fail(res) {
// File does not exist or other error
console.error(res)
}
})
// Synchronization interface
try {
fs.accessSync(`${wx.env.USER_DATA_PATH}/hello.txt`)
} catch(e) {
console.error(e)
}.appendFile
TIP
The API usage is as follows: FileSystemManager.appendFile(Object object)
Functional description: Append content to the end of the file
Parameters and descriptions: Object object。
Properties Type Default value Required Description filePath string - Yes The file path to which the content is to be appended. data string/ArrayBuffer - Yes The text or binary data to be appended. encoding string utf-8 No Specify the character encoding for writing to the file. success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) Legal values
Value Description ascii - base64 - binary - hex - ucs2/ucs-2/utf16le/utf-16le Read in little endian utf-8/utf8 - latin1 - object.fail callback function parameter: Object res。
Properties Type Description errMsg string Error message Legal values
Value Description fail no such file or directory ${ path}The specified filePath file does not exist fail illegal operation on a directory, open "${ filePath}"The specified filePath is an existing directory fail permission denied, open ${ dirPath}The specified filePath path does not have write permission fail sdcard not mounted The specified filePath is an existing directory Sample code:
const fs = wx.getFileSystemManager()
fs.appendFile({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
data: 'some text',
encoding: 'utf8',
success(res) {
console.log(res)
},
fail(res) {
console.error(res)
}
})
// sync
try {
fs.appendFileSync(`${wx.env.USER_DATA_PATH}/hello.txt`, 'some text', 'utf8')
} catch(e) {
console.error(e)
}.appendFileSync
TIP
The API usage is as follows: FileSystemManager.appendFileSync(string filePath, string|ArrayBuffer data, string encoding)
Functional description: FileSystemManager.appendFile The synchronous version
Parameters and descriptions:
- string filePath: The file path to which the content is to be appended.
- string|ArrayBuffer data: The text or binary data to be appended.
- string encoding: Specify the character encoding for writing to the file.
Legal values
Value Description ascii - base64 - binary - hex - ucs2/ucs-2/utf16le/utf-16le Read in little endian utf-8/utf8 - latin1 - Sample code:
const fs = wx.getFileSystemManager()
fs.appendFile({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
data: 'some text',
encoding: 'utf8',
success(res) {
console.log(res)
},
fail(res) {
console.error(res)
}
})
// sync
try {
fs.appendFileSync(`${wx.env.USER_DATA_PATH}/hello.txt`, 'some text', 'utf8')
} catch(e) {
console.error(e)
}.close
TIP
The API usage is as follows: FileSystemManager.close(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Close the file
Parameters and descriptions: Object object。
Properties Type Default value Required Description fd string - Yes The file descriptor that needs to be closed, fd is obtained through FileSystemManager.open FileSystemManager.openSync Interface success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) Sample code:
const fs = wx.getFileSystemManager()
// open file
fs.open({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
flag: 'a+',
success(res) {
// close file
fs.close({
fd: res.fd
})
}
}).closeSync
TIP
The API usage is as follows: undefined FileSystemManager.closeSync(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Synchronously close the file
Parameters and descriptions: Object object。
Properties Type Default value Required Description fd string - Yes The file descriptor that needs to be closed, fd is obtained through FileSystemManager.open FileSystemManager.openSync Interface Return value: undefined。
Sample code:
const fs = wx.getFileSystemManager()
const fd = fs.openSync({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
flag: 'a+'
})
// close file
fs.closeSync({fd: fd}).copyFile
TIP
The API usage is as follows: FileSystemManager.copyFile(Object object)
Functional description: Copy the file
Parameters and descriptions: Object object。
Properties Type Default value Required Description srcPath string - Yes Source file path, can only be ordinary file destPath string - Yes Destination file path, supports local path success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) - object.fail callback function parameter: Object res。
Properties Type Description errMsg string Error message
- object.fail callback function parameter: Object res。
Legal values
Value Description fail permission denied, copyFile ${ srcPath} -> ${destPath}Specified destination file path does not have write permission fail no such file or directory, copyFile ${ srcPath} -> ${destPath}The source file does not exist, or the upper directory of the destination file path does not exist Sample code:
const fs = wx.getFileSystemManager()
fs.copyFile({
srcPath: `${wx.env.USER_DATA_PATH}/hello.txt`,
destPath: `${wx.env.USER_DATA_PATH}/hello_copy.txt`
success(res) {
console.log(res)
},
fail(res) {
console.error(res)
}
})
// sync api
try {
fs.copyFileSync(
`${wx.env.USER_DATA_PATH}/hello.txt`,
`${wx.env.USER_DATA_PATH}/hello_copy.txt`
)
} catch(e) {
console.error(e)
}.copyFileSync
TIP
The API usage is as follows: FileSystemManager.copyFileSync(string srcPath, string destPath)
Functional description: FileSystemManager.copyFile The synchronous version
Parameters and descriptions:
- string srcPath: The source file path, can only be ordinary file.
- string destPath: Destination file path.
Sample code:
const fs = wx.getFileSystemManager()
fs.copyFile({
srcPath: `${wx.env.USER_DATA_PATH}/hello.txt`,
destPath: `${wx.env.USER_DATA_PATH}/hello_copy.txt`
success(res) {
console.log(res)
},
fail(res) {
console.error(res)
}
})
// sync api
try {
fs.copyFileSync(
`${wx.env.USER_DATA_PATH}/hello.txt`,
`${wx.env.USER_DATA_PATH}/hello_copy.txt`
)
} catch(e) {
console.error(e)
}.getFileInfo
TIP
The API usage is as follows: FileSystemManager.getFileInfo(Object object)
- Functional description: Get the local temporary file or local cache file information under the applet.
- Parameters and descriptions: Object object。
Properties Type Default value Required Description filePath string - Yes The file path to read digestAlgorithm string md5 No Algorithm for calculating file digest success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) - Legal values
Value Description md5 md5 algorithm sha1 sha1 algorithm
- Legal values
- object.success callback function parameters: Object res。
Properties Type Description size number Local file size, in bytes digest string File digest calculated according to the passed digestAlgorithm - object.fail callback function parameter: Object res。
Properties Type Description errMsg string Error message - Legal values
Value Description fail file not exist The specified filePath cannot find the file no such file or directory ${ path}The file/directory does not exist, or the parent directory of the target file path does not exist Input/output error The input and output streams are not available permission denied Permission error, the file is read-only or write-only Path permission denied The passed path has no permissions not a directory The path specified by dirPath is not a directory, which is common when the parent path of the specified write path is a file Invalid argument Invalid parameters, you can check whether length or offset is out of bounds excced max concurrent fd limit The number of fds has reached the upper limit
.fstat
TIP
The API usage is as follows: FileSystemManager.fstat(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Get the status information of the file.
Parameters and descriptions: Object object。
Properties Type Default value Required Description fd string - Yes The file descriptor that needs to be closed, fd is obtained through FileSystemManager.open FileSystemManager.openSync Interface success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) object.success callback function parameters: Object res。
Properties Type Description stats stats Stats object, containing the status information of the file. Sample code:
const fs = wx.getFileSystemManager()
// open files
fs.open({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
flag: 'a+',
success(res) {
// get information
fs.fstat({
fd: res.fd,
success(res) {
console.log(res.stats)
}
})
}
}).fstatSync
TIP
The API usage is as follows: Stats FileSystemManager.fstatSync(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Synchronously get the status information of the file.
Parameters and descriptions: Object object。
Properties Type Default value Required Description fd string - Yes The file descriptor that needs to be closed, fd is obtained through FileSystemManager.open FileSystemManager.openSync Interface Return value: Stats, Stats object, containing the status information of the file.
Sample code:
const fs = wx.getFileSystemManager()
const fd = fs.openSync({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
flag: 'a+'
})
const stats = fs.fstatSync({fd: fd})
console.log(stats).ftruncate
TIP
The API usage is as follows: FileSystemManager.ftruncate(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Truncate the file contents.
Parameters and descriptions: Object object。
Properties Type Default value Required Description fd string - Yes The file descriptor that needs to be closed, fd is obtained through FileSystemManager.open FileSystemManager.openSync Interface length number - Yes Truncation position, default 0. If length is less than the file length (bytes), only the first length bytes will be retained in the file, and the rest will be deleted; if length is greater than the file length, it will be extended, and the extended part will be filled with null bytes ('\0') success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) Sample code:
const fs = wx.getFileSystemManager()
// Open the file
fs.open({
filePath: ${wx.env.USER_DATA_PATH}/hello.txt,
flag: 'a+',
success(res) {
//Truncate the file content.
fs.ftruncate({
fd: res.fd,
length: 10, // Truncate the file starting from the 10th byte
success(res) {
console.log(res)
}
})
}
}).ftruncateSync
TIP
The API usage is as follows: undefined FileSystemManager.ftruncateSync(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Truncate the file contents.
Parameters and descriptions: Object object。
Properties Type Default value Required Description fd string - Yes The file descriptor that needs to be closed, fd is obtained through FileSystemManager.open FileSystemManager.openSync Interface length number - Yes Truncation position, default 0. If length is less than the file length (bytes), only the first length bytes will be retained in the file, and the rest will be deleted; if length is greater than the file length, it will be extended, and the extended part will be filled with null bytes ('\0') Parameters and descriptions: undefined。
Sample code:
const fs = wx.getFileSystemManager()
const fd = fs.openSync({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
flag: 'a+'
})
fs.ftruncateSync({
fd: fd,
length: 10 // from the 10th byte
}).getSavedFileList
TIP
The API usage is as follows: FileSystemManager.getSavedFileList(Object object)
Functional description: Get the list of local cache files saved under this applet.
Parameters and descriptions: Object object。
Properties Type Default value Required Description success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) object.success callback function parameters: Object res。
Properties Type Description fileList Array.< Object>File array, each item is a FileItem The structure of res.fileList
Properties Type Description filePath string Local path size number Local file size, in bytes createTime number The timestamp when the file is saved, the number of seconds from 1970/01/01 08:00:00 to the current time
.mkdir
TIP
The API usage is as follows: FileSystemManager.mkdir(Object object)
Functional description: Judge whether the file/directory exists
Parameters and descriptions: Object object。
Properties Type Default value Required Description dirPath string - Yes Directory path to create recursive boolean false No Whether to create the directory after recursively creating the parent directory of the directory. If the corresponding parent directory already exists, it will not be created. If dirPath is a/b/c/d and recursive is true, the a directory will be created, and then the b directory will be created under the a directory, and so on until the d directory under the a/b/c directory is created. success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) object.fail callback function parameter: Object res。
Properties Type Description errMsg string Error message Legal values
Value Description fail no such file or directory ${ dirPath}Parent directory does not exist fail permission denied, open ${ dirPath}The specified filePath path does not have write permission fail file already exists ${ dirPath}There is a file or directory with the same name Sample code:
const fs = wx.getFileSystemManager()
fs.mkdir({
dirPath: `${wx.env.USER_DATA_PATH}/example`,
recursive: false,
success(res) {
console.log(res)
},
fail(res) {
console.error(res)
}
})
// sync api
try {
fs.mkdirSync(`${wx.env.USER_DATA_PATH}/example`, false)
} catch(e) {
console.error(e)
}.mkdirSync
TIP
The API usage is as follows: FileSystemManager.mkdirSync(string dirPath, boolean recursive)
Functional description: FileSystemManager.mkdir The synchronous version
Parameters and descriptions:
- string dirPath：Directory path to create
- boolean recursive：Whether to create the directory after recursively creating the parent directory of the directory. If the corresponding parent directory already exists, it will not be created. If dirPath is a/b/c/d and recursive is true, the a directory will be created, and then the b directory will be created under the a directory, and so on until the d directory under the a/b/c directory is created.
Sample code:
const fs = wx.getFileSystemManager()
fs.mkdir({
dirPath: `${wx.env.USER_DATA_PATH}/example`,
recursive: false,
success(res) {
console.log(res)
},
fail(res) {
console.error(res)
}
})
// sync api
try {
fs.mkdirSync(`${wx.env.USER_DATA_PATH}/example`, false)
} catch(e) {
console.error(e)
}.open
TIP
The API usage is as follows: FileSystemManager.open(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Open the file and return the file descriptor
Parameters and descriptions: Object object。
Properties Type Default value Required Description filePath string - Yes File path (local path) flag string r No File system flag, default value: r success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) Flag legal value
Legal value Description a Open the file for appending. If the file does not exist, create the file ax Similar to 'a', but if the path exists, it will fail a+ Open the file for reading and appending. If the file does not exist, create the file ax+ Similar to 'a+', but if the path exists, it will fail as Open the file for appending (in synchronous mode). If the file does not exist, create the file as+ Open the file for reading and appending (in synchronous mode). If the file does not exist, create the file r Open the file for reading. If the file does not exist, an exception will occur r+ Open the file for reading and writing. If the file does not exist, an exception will occur w Open the file for writing. Create the file if it does not exist, and truncate it if it exists wx Similar to 'w', but fails if the path exists w+ Open the file for reading and writing. Create the file if it does not exist, and truncate it if it exists wx+ Similar to 'w+', but fails if the path exists object.success callback function parameters: Object res。
Properties Type Description fd string File descriptor Sample code:
const fs = wx.getFileSystemManager()
fs.open({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
flag: 'a+',
success(res) {
console.log(res.fd)
}
}).openSync
TIP
The API usage is as follows: string FileSystemManager.openSync(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Synchronously open the file and return the file descriptor.
Parameters and descriptions: Object object。
Properties Type Default value Required Description filePath string - Yes File path (local path) flag string r No File system flag, default value: r Flag legal value
Legal value Description a Open the file for appending. If the file does not exist, create the file ax Similar to 'a', but if the path exists, it will fail a+ Open the file for reading and appending. If the file does not exist, create the file ax+ Similar to 'a+', but if the path exists, it will fail as Open the file for appending (in synchronous mode). If the file does not exist, create the file as+ Open the file for reading and appending (in synchronous mode). If the file does not exist, create the file r Open the file for reading. If the file does not exist, an exception will occur r+ Open the file for reading and writing. If the file does not exist, an exception will occur w Open the file for writing. Create the file if it does not exist, and truncate it if it exists wx Similar to 'w', but fails if the path exists w+ Open the file for reading and writing. Create the file if it does not exist, and truncate it if it exists wx+ Similar to 'w+', but fails if the path exists Return value: string，File descriptor
Sample code:
const fs = wx.getFileSystemManager()
const fd = fs.openSync({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
flag: 'a+'
})
console.log(fd).read
TIP
The API usage is as follows: FileSystemManager.read(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Read the file
Parameters and descriptions: Object object。
Properties Type Default value Required Description fd string - Yes The file descriptor that needs to be closed, fd is obtained through FileSystemManager.open FileSystemManager.openSync Interface arrayBuffer ArrayBuffer - Yes The buffer to which the data is written, must be an ArrayBuffer instance offset number - No The write offset in the buffer, default 2 length number - No The number of bytes to read from the file, default 2 position number r No The starting position of the file to read, if not passed or null, will read from the current file pointer position, if position is a positive integer, the file pointer position will remain unchanged and read the file from position. success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) object.success callback function parameters: Object res。
Properties Type Description bytesRead number The actual number of bytes read arrayBuffer ArrayBuffer The object of the buffer area to be written, that is, the arrayBuffer of the interface input parameter Sample code:
const fs = wx.getFileSystemManager()
const ab = new ArrayBuffer(1024)
// open the file
fs.open({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
flag: 'a+',
success(res) {
// read file to ArrayBuffer
fs.read({
fd: res.fd,
arrayBuffer: ab,
length: 10,
success(res) {
console.log(res)
}
})
}
}).readSync
TIP
The API usage is as follows: ReadResult FileSystemManager.readSync(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Read the file
Parameters and descriptions: Object object。
Properties Type Default value Required Description fd string - Yes The file descriptor that needs to be closed, fd is obtained through FileSystemManager.open FileSystemManager.openSync Interface arrayBuffer ArrayBuffer - Yes The buffer to which the data is written, must be an ArrayBuffer instance offset number - No The write offset in the buffer, default 2 length number - No The number of bytes to read from the file, default 2 position number r No The starting position of the file to read, if not passed or null, will read from the current file pointer position, if position is a positive integer, the file pointer position will remain unchanged and read the file from position. Return value: ReadResult File reading results. Through
Sample code:
const fs = wx.getFileSystemManager()
const ab = new ArrayBuffer(1024)
const fd = fs.openSync({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
flag: 'a+'
})
const res = fs.readSync({
fd: fd,
arrayBuffer: ab,
length: 10
})
console.log(res).readCompressedFile
TIP
The API usage is as follows: FileSystemManager.readCompressedFile(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Read the local file contents of the specified compression type.
Parameters and descriptions: Object object。
Properties Type Default value Required Description filePath string - Yes The path of the file to be read (local user file or code package file) compressionAlgorithm string r Yes File compression type, currently only supports br success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) The legal values
Legal value Description br brotli compressed file object.success callback function parameters: Object res。
Properties Type Description data ArrayBuffer file content Sample code:
const fs = wx.getFileSystemManager()
//
fs.readCompressedFile({
filePath: '${wx.env.USER_DATA_PATH}/hello.br',
compressionAlgorithm: 'br',
success(res) {
console.log(res.data)
},
fail(res) {
console.log('readCompressedFile fail', res)
}
})
// async api
const data = fs.readCompressedFileSync({
filePath: '${wx.env.USER_DATA_PATH}/hello.br',
compressionAlgorithm: 'br',
})
console.log(data).readCompressedFileSync
TIP
The API usage is as follows: ArrayBuffer FileSystemManager.readCompressedFileSync(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Synchronously read the local file contents of the specified compression type.
Parameters and descriptions: Object object。
Properties Type Default value Required Description filePath string - Yes The path of the file to be read (local user file or code package file) compressionAlgorithm string r Yes File compression type, currently only supports br The legal values
Legal value Description br brotli compressed file Return value: ArrayBuffer，File reading results
Sample code:
const fs = wx.getFileSystemManager()
//
fs.readCompressedFile({
filePath: '${wx.env.USER_DATA_PATH}/hello.br',
compressionAlgorithm: 'br',
success(res) {
console.log(res.data)
},
fail(res) {
console.log('readCompressedFile fail', res)
}
})
// async api
const data = fs.readCompressedFileSync({
filePath: '${wx.env.USER_DATA_PATH}/hello.br',
compressionAlgorithm: 'br',
})
console.log(data).readdir
TIP
The API usage is as follows: FileSystemManager.readdir(Object object)
Functional description: Read the list of files in the directory
Parameters and descriptions: Object object。
Properties Type Default value Required Description dirPath string - Yes directory path to read success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) object.success callback function parameters: Object res。
Properties Type Description files Array.< string>array of file names under the specified directory. object.fail callback function parameter: Object res。
Properties Type Description errMsg string Error message Legal values
Value Description fail no such file or directory ${ dirPath}directory does not exist fail not a directory ${ dirPath}dirPath is not a directory fail permission denied, open ${ dirPath}the specified filePath path has no read permission Sample code:
TIP
the readdir interface cannot access the file system root path (wxfile://).
const fs = wx.getFileSystemManager()
fs.readdir({
dirPath: `${wx.env.USER_DATA_PATH}/example`,
success(res) {
console.log(res.files)
},
fail(res) {
console.error(res)
}
})
// sync api
try {
const res = fs.readdirSync(`${wx.env.USER_DATA_PATH}/example`)
console.log(res)
} catch(e) {
console.error(e)
}.readdirSync
TIP
The API usage is as follows: Array.<string> FileSystemManager.readdirSync(string dirPath)
This API is supported by mini programs, but not by mini games.
Functional description: FileSystemManager.readdirThe synchronous version
Parameters and descriptions: string dirPath, directory path to read.
Return value: Array.<
string> files, array of file names under the specified directory.Sample code:
const fs = wx.getFileSystemManager()
fs.readdir({
dirPath: `${wx.env.USER_DATA_PATH}/example`,
success(res) {
console.log(res.files)
},
fail(res) {
console.error(res)
}
})
// sync api
try {
const res = fs.readdirSync(`${wx.env.USER_DATA_PATH}/example`)
console.log(res)
} catch(e) {
console.error(e)
}.readFile
TIP
The API usage is as follows: FileSystemManager.readFile(Object object)
Functional description: read local file content. The upper limit of a single file size is 100M
Parameters and descriptions: Object object
Properties Type Default value Required Description filePath string - Yes path of the file to read encoding string - No specify the character encoding of the file to be read. If encoding is not passed, the binary content of the file is read in ArrayBuffer format success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) Legal values
Value Description ascii - base64 - binary - hex - ucs2/ucs-2/utf16le/utf-16le Read in little endian utf-8/utf8 - latin1 - object.success callback function parameters: Object res。
Properties Type Description data string/ArrayBuffer file content object.fail callback function parameter: Object res。
Properties Type Description errMsg string Error message Legal values
Value Description fail no such file or directory, open ${ filePath}the directory where the specified filePath is located does not exist fail permission denied, open ${ dirPath}the specified filePath path has no read permission Sample code:
const fs = wx.getFileSystemManager()
fs.readFile({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
encoding: 'utf8',
position: 0,
success(res) {
console.log(res.data)
},
fail(res) {
console.error(res)
}
})
// sync api
try {
const res = fs.readFileSync(`${wx.env.USER_DATA_PATH}/hello.txt`, 'utf8', 0)
console.log(res)
} catch(e) {
console.error(e)
}.readFileSync
TIP
The API usage is as follows: string|ArrayBuffer FileSystemManager.readFileSync(string filePath, string encoding)
This API is supported by mini programs, but not by mini games.
Functional description: FileSystemManager.readFileread local file content. The upper limit of a single file size is 100M
Parameters and descriptions:
- string filePath：path of the file to read
- string encoding：specify the character encoding of the file to be read. If encoding is not passed, the binary content of the file is read in ArrayBuffer format
Legal values
Value Description ascii - base64 - binary - hex - ucs2/ucs-2/utf16le/utf-16le Read in little endian utf-8/utf8 - latin1 - Return value: string|ArrayBuffer data，Read the local file content
Sample code:
const fs = wx.getFileSystemManager()
fs.readFile({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
encoding: 'utf8',
position: 0,
success(res) {
console.log(res.data)
},
fail(res) {
console.error(res)
}
})
// async api
try {
const res = fs.readFileSync(`${wx.env.USER_DATA_PATH}/hello.txt`, 'utf8', 0)
console.log(res)
} catch(e) {
console.error(e)
}.readZipEntry
TIP
The API usage is as follows: FileSystemManager.readZipEntry(Object object)
Functional description: Read the files in the compressed package
Parameters and descriptions: Object object
Properties Type Default value Required Description filePath string - Yes the path of the compressed package to be read (local path) encoding string - No unified specification of the character encoding of the read file, only valid when the entries value is 'all'. If the entries value is 'all' and encoding is not passed, the binary content of the file is read in ArrayBuffer format entries Array.< Object>/'all'- Yes The list of files in the compressed package to be read (when 'all' is passed, it means reading all files in the compressed package) success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) Legal values
Value Description ascii - base64 - binary - hex - ucs2/ucs-2/utf16le/utf-16le Read in little endian utf-8/utf8 - latin1 - entries structure attribute
Structure properties Type Default value Required Description path string - Yes File path in the compressed package encoding string - No Specify the character encoding of the file to be read. If encoding is not passed, the binary content of the file is read in ArrayBuffer format. The legal value is the same as encoding position number - No Start reading from the specified position of the file. If not specified, read from the file header. The reading range should be a left-closed and right-open interval position, position+length. Valid range: [0, fileLength - 1]. Unit: byte length number - No Specify the length of the file. If not specified, read to the end of the file. Valid range: [1, fileLength]. Unit: byte object.success callback function parameters: Object res。
Properties Type Description entries Object File reading result. res.entries is an object, key is the file path, value is an object FileItem, which represents the reading result of the file. Each FileItem contains data (file content) and errMsg (error message) attributes - entries structure attribute
Structure properties Type Description path string File path - path structure attribute
Structure properties Type Description data string/ArrayBuffer file content errMsg string Error message Sample code:
const fs = wx.getFileSystemManager()
// Read one or multiple files within a zip.
fs.readZipEntry({
filePath: 'wxfile://from/to.zip',
entries: [{
path: 'some_folder/my_file.txt', // File path within the zip
encoding: 'utf-8', // Specifies the character encoding for reading the file. If 'encoding' is not passed, the file's binary content is read in ArrayBuffer format
position: 0, // Start reading from a specified position in the file; if not specified, reading begins from the start of the file. The reading range should be a left-closed and right-open interval [position, position+length). The valid range is [0, fileLength - 1] in bytes.
length: 10000, // Specify the length of the file. If not specified, reading continues until the end of the file. The valid range is [1, fileLength] in bytes.
}, {
path: 'other_folder/orther_file.txt', // File path within the zip
}],
success(res) {
console.log(res.entries)
// res.entries === {
// 'some_folder/my_file.txt': {
// errMsg: 'readZipEntry:ok',
// data: 'xxxxxx'
// },
// 'other_folder/orther_file.txt': {
// data: (ArrayBuffer)
// }
// }
},
fail(res) {
console.log(res.errMsg)
},
})
// Reads all files within the zip. A unified 'encoding' can be specified. 'Position' and 'length' can no longer be specified and default to 0 and the file length, respectively.
fs.readZipEntry({
filePath: 'wxfile://from/to.zip',
entries: 'all'
encoding: 'utf-8', // Uniformly specifies the character encoding for reading the file. If 'encoding' is not passed, the file's binary content is read in ArrayBuffer format.
success(res) {
console.log(res.entries)
// res.entries === {
// 'some_folder/my_file.txt': {
// errMsg: 'readZipEntry:ok',
// data: 'xxxxxx'
// },
// 'other_folder/orther_file.txt': {
// errMsg: 'readZipEntry:ok',
// data: 'xxxxxx'
// }
// }
},
fail(res) {
console.log(res.errMsg)
},
}).removeSavedFile
TIP
The API usage is as follows: FileSystemManager.removeSavedFile(Object object)
Functional description: Delete the local cache files saved under this applet
Parameters and descriptions: Object object。
Properties Type Default value Required Description filePath string - Yes The file path to be deleted success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) object.fail callback function parameter: Object res。
Properties Type Description errMsg string Error message Legal values
Value Description fail file not exist The specified tempFilePath cannot find the file
.rename
TIP
The API usage is as follows: FileSystemManager.rename(Object object)
Functional description: Rename the file. You can move the file from oldPath to newPath
Parameters and descriptions: Object object。
Properties Type Default value Required Description oldPath string - Yes The source file path can be a normal file or directory, and supports local paths newPath string - Yes The new file path supports local paths success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) object.fail callback function parameter: Object res。
Properties Type Description errMsg string Error message Legal values
Value Description fail permission denied, rename ${ oldPath} -> ${newPath}Specify that the source file or target file does not have write permissions fail no such file or directory, rename ${ oldPath} -> ${newPath}The source file does not exist, or the upper directory of the destination file path does not exist Sample code:
const fs = wx.getFileSystemManager()
fs.rename({
oldPath: `${wx.env.USER_DATA_PATH}/hello.txt`,
newPath: `${wx.env.USER_DATA_PATH}/hello_new.txt`,
success(res) {
console.log(res)
},
fail(res) {
console.error(res)
}
})
// sync api
try {
const res = fs.renameSync(
`${wx.env.USER_DATA_PATH}/hello.txt`,
`${wx.env.USER_DATA_PATH}/hello_new.txt`
)
console.log(res)
} catch(e) {
console.error(e)
}.renameSync
TIP
The API usage is as follows: FileSystemManager.renameSync(string oldPath, string newPath)
This API is supported by mini programs, but not by mini games.
Functional description: FileSystemManager.renameThe synchronous version
Parameters and descriptions:
- string oldPath：The source file path can be a normal file or directory, and supports local paths
- string newPath：The new file path supports local paths
Sample code:
const fs = wx.getFileSystemManager()
fs.rename({
oldPath: `${wx.env.USER_DATA_PATH}/hello.txt`,
newPath: `${wx.env.USER_DATA_PATH}/hello_new.txt`,
success(res) {
console.log(res)
},
fail(res) {
console.error(res)
}
})
// async api
try {
const res = fs.renameSync(
`${wx.env.USER_DATA_PATH}/hello.txt`,
`${wx.env.USER_DATA_PATH}/hello_new.txt`
)
console.log(res)
} catch(e) {
console.error(e)
}.rmdir
TIP
The API usage is as follows: FileSystemManager.rmdir(Object object)
Functional description: Delete the directory
Parameters and descriptions: Object object。
Properties Type Default value Required Description dirPath string - Yes The directory path to be deleted recursive boolean false No Whether to recursively delete the directory. If true, delete the directory and all subdirectories and files under the directory success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) object.fail callback function parameter: Object res。
Properties Type Description errMsg string Error message Legal values
Value Description fail no such file or directory ${ dirPath}directory does not exist fail directory not empty The directory is not empty fail permission denied, open ${ dirPath}The specified dirPath path does not have write permissions Sample code:
const fs = wx.getFileSystemManager()
fs.rmdir({
dirPath: `${wx.env.USER_DATA_PATH}/example`,
recursive: false,
success(res) {
console.log(res)
},
fail(res) {
console.error(res)
}
})
// sync api
try {
const res = fs.rmdirSync(`${wx.env.USER_DATA_PATH}/example`, false)
console.log(res)
} catch(e) {
console.error(e)
}.rmdirSync
TIP
The API usage is as follows: FileSystemManager.rmdirSync(string dirPath, boolean recursive)
Functional description: FileSystemManager.rmdir The synchronous version
Parameters and descriptions:
- string dirPath: The directory path to be deleted
- boolean recursive：Whether to recursively delete the directory. If true, delete the directory and all subdirectories and files under the directory
Sample code:
const fs = wx.getFileSystemManager()
fs.rmdir({
dirPath: `${wx.env.USER_DATA_PATH}/example`,
recursive: false,
success(res) {
console.log(res)
},
fail(res) {
console.error(res)
}
})
// sync api
try {
const res = fs.rmdirSync(`${wx.env.USER_DATA_PATH}/example`, false)
console.log(res)
} catch(e) {
console.error(e)
}.saveFile
TIP
The API usage is as follows: FileSystemManager.saveFile(Object object)
Functional description: Save temporary files locally. This interface will move temporary files, so after the call is successful, tempFilePath will not be available
Parameters and descriptions: Object object。
Properties Type Default value Required Description tempFilePath string - Yes Temporary storage file path filePath string - No File path to be stored success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) object.success callback function parameters: Object res。
Properties Type Description savedFilePath number The file path after storage object.fail callback function parameter: Object res。
Properties Type Description errMsg string Error message Legal values
Value Description fail tempFilePath file not exist The specified tempFilePath cannot find the file fail permission denied, open "${ filePath}"The specified filePath path does not have write permission fail no such file or directory "${ dirPath}"Parent directory does not exist
.saveFileSync
TIP
The API usage is as follows: number FileSystemManager.saveFileSync(string tempFilePath, string filePath)
- Functional description: Synchronous version of FileSystemManager.saveFile
- Parameters and descriptions:
- string tempFilePath：Temporary storage file path
- string filePath：File path to be stored
- Return value: number savedFilePath，The file path after storage
.stat
TIP
The API usage is as follows: FileSystemManager.stat(Object object)
Functional description: Get the file Stats object
Parameters and descriptions: Object object。
Properties Type Default value Required Description path string - Yes File/directory path recursive boolean false No Whether to recursively obtain Stats information for each file in the directory success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) object.success callback function parameters: Object res。
Properties Type Description stats Stats/Object When recursive is false, res.stats is a Stats object. When recursive is true and path is a directory path, res.stats is an Object, the key is the relative path of the root path of path, and the value is the Stats object corresponding to the path object.fail callback function parameter: Object res。
Properties Type Description errMsg string Error message Legal values
Value Description fail permission denied, open ${ path}The specified path path has no read permission fail no such file or directory ${ path}The file does not exist Sample code:
When recursive is false
// synchronous
let fs = wx.getFileSystemManager()
fs.stat({
path: `${wx.env.USER_DATA_PATH}/testDir`,
success: res => {
console.log(res.stats.isDirectory())
}
})
// sync
fs.statSync(`${wx.env.USER_DATA_PATH}/testDir`, false)When recursive is true
let fs = wx.getFileSystemManager()
// sync
fs.stat({
path: `${wx.env.USER_DATA_PATH}/testDir`,
recursive: true,
success: res => {
Object.keys(res.stats).forEach(path => {
let stats = res.stats[path]
console.log(path, stats.isDirectory())
})
}
})
// synchronous
fs.statSync(`${wx.env.USER_DATA_PATH}/testDir`, true).statSync
TIP
The API usage is as follows: Stats|Object FileSystemManager.statSync(string path, boolean recursive)
Functional description: FileSystemManager.stat The synchronous version
Parameters and descriptions:
- string path：File/directory path
- boolean recursive：Whether to recursively obtain Stats information for each file in the directory
Parameters and descriptions: Stats|Object stats，When recursive is false, res.stats is a Stats object. When recursive is true and path is a directory path, res.stats is an Object, the key is the relative path of the root path of path, and the value is the Stats object corresponding to the path
Sample code:
When recursive is false
// synchronous
let fs = wx.getFileSystemManager()
fs.stat({
path: `${wx.env.USER_DATA_PATH}/testDir`,
success: res => {
console.log(res.stats.isDirectory())
}
})
// sync
fs.statSync(`${wx.env.USER_DATA_PATH}/testDir`, false)When recursive is true
let fs = wx.getFileSystemManager()
// syn
fs.stat({
path: `${wx.env.USER_DATA_PATH}/testDir`,
recursive: true,
success: res => {
Object.keys(res.stats).forEach(path => {
let stats = res.stats[path]
console.log(path, stats.isDirectory())
})
}
})
// synchronous
fs.statSync(`${wx.env.USER_DATA_PATH}/testDir`, true).truncate
TIP
The API usage is as follows: FileSystemManager.truncate(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Truncate the file contents.
Parameters and descriptions: Object object。
Properties Type Default value Required Description filePath string - Yes The file path to be truncated (local path) length number 0 No Truncation position, default 0. If length is less than the file length (bytes), only the first length bytes will be retained in the file, and the rest will be deleted; if length is greater than the file length, it will be extended, and the extended part will be filled with null bytes ('\0') success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) Sample code:
const fs = wx.getFileSystemManager()
fs.truncate({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
length: 10, // from ten bytes to the end
success(res) {
console.log(res)
}
}).truncateSync
TIP
The API usage is as follows: undefined FileSystemManager.truncateSync(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Truncate the file content (Synchronous version of truncate)
Parameters and descriptions: Object object。
Properties Type Default value Required Description filePath string - Yes The file path to be truncated (local path) length number 0 No Truncation position, default 0. If length is less than the file length (bytes), only the first length bytes will be retained in the file, and the rest will be deleted; if length is greater than the file length, it will be extended, and the extended part will be filled with null bytes ('\0') Return value: undefined。
Sample code:
const fs = wx.getFileSystemManager()
fs.truncateSync({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
length: 10, // from ten bytes to the end
}).unlink
TIP
The API usage is as follows: FileSystemManager.unlink(Object object)
Functional description: Delete the file
Parameters and descriptions: Object object。
Properties Type Default value Required Description filePath string - Yes The file path to be deleted success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) object.fail callback function parameter: Object res。
Properties Type Description errMsg string Error message Legal values
Value Description fail permission denied, open ${ path}The specified path path has no read permission fail no such file or directory ${ path}The file does not exist fail operation not permitted, unlink ${ filePath}The passed filePath is a directory Sample code:
const fs = wx.getFileSystemManager()
fs.unlink({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
success(res) {
console.log(res)
},
fail(res) {
console.error(res)
}
})
// sync
try {
const res = fs.unlinkSync(`${wx.env.USER_DATA_PATH}/hello.txt`)
console.log(res)
} catch(e) {
console.error(e)
}.unlinkSync
TIP
The API usage is as follows: FileSystemManager.unlinkSync(string filePath)
Functional description: FileSystemManager.unlink The synchronous version
Parameters and descriptions: string filePath: The file path to be deleted
Sample code:
const fs = wx.getFileSystemManager()
fs.unlink({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
success(res) {
console.log(res)
},
fail(res) {
console.error(res)
}
})
try {
const res = fs.unlinkSync(`${wx.env.USER_DATA_PATH}/hello.txt`)
console.log(res)
} catch(e) {
console.error(e)
}.unzip
TIP
The API usage is as follows: FileSystemManager.unzip(Object object)
Functional description: Unzip the file
Parameters and descriptions: Object object。
Properties Type Default value Required Description zipFilePath string - Yes The source file path can only be a zip compressed file targetPath string - Yes The target directory path success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) object.fail callback function parameter: Object res。
Properties Type Description errMsg string Error message Legal values
Value Description fail permission denied, open ${ path}Specified destination file path does not have write permission fail no such file or directory ${ path}The source file does not exist, or the upper directory of the destination file path does not exist Sample code:
const fs = wx.getFileSystemManager()
fs.unzip({
zipFilePath: `${wx.env.USER_DATA_PATH}/example.zip`,
targetPath: '${wx.env.USER_DATA_PATH}/example',
success(res) {
console.log(res)
},
fail(res) {
console.error(res)
}
}).write
TIP
The API usage is as follows: FileSystemManager.write(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Write the file
Parameters and descriptions: Object object
Properties Type Default value Required Description fd string - Yes The file descriptor that needs to be closed, fd is obtained through FileSystemManager.open FileSystemManager.openSync Interface data string/ArrayBuffer - Yes The text or binary data to be written offset number - No Only valid when the data type is ArrayBuffer, determines the part to be written in arrayBuffe, that is, the index in arrayBuffer, the default is 2 length number - No Only valid when the data type is ArrayBuffer, specifies the number of bytes to be written, the default is the number of bytes remaining after arrayBuffer starts at offset bytes from 2 encoding string utf8 No Specify the character encoding for writing to the file. position number r No Specifies the offset at the beginning of the file, that is, the position where the data is to be written. When position is not passed or a value other than the Number type is passed, the data will be written to the current pointer position success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) Legal values
Value Description ascii - base64 - binary - hex - ucs2/ucs-2/utf16le/utf-16le Read in little endian utf-8/utf8 - latin1 - object.success callback function parameters: Object res。
Properties Type Description bytesWritten number The number of bytes actually written to the file (note that the number of bytes written is not necessarily the same as the number of string characters written) Sample code:
const fs = wx.getFileSystemManager()
// open the file
fs.open({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
flag: 'a+',
success(res) {
// write the file
fs.write({
fd: res.fd,
data: 'some text',
success(res) {
console.log(res.bytesWritten)
}
})
}
}).writeSync
TIP
The API usage is as follows: FileSystemManager.writeFile(Object object)
This API is supported by mini programs, but not by mini games.
Functional description: Write the file synchronously
Parameters and descriptions: Object object
Properties Type Default value Required Description fd string - Yes The file descriptor that needs to be closed, fd is obtained through FileSystemManager.open FileSystemManager.openSync Interface data string/ArrayBuffer - Yes The text or binary data to be written offset number - No Only valid when the data type is ArrayBuffer, determines the part to be written in arrayBuffe, that is, the index in arrayBuffer, the default is 2 length number - No Only valid when the data type is ArrayBuffer, specifies the number of bytes to be written, the default is the number of bytes remaining after arrayBuffer starts at offset bytes from 2 encoding string utf8 No Specify the character encoding for writing to the file. position number r No Specifies the offset at the beginning of the file, that is, the position where the data is to be written. When position is not passed or a value other than the Number type is passed, the data will be written to the current pointer position success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) Legal values
Value Description ascii - base64 - binary - hex - ucs2/ucs-2/utf16le/utf-16le Read in little endian utf-8/utf8 - latin1 - object.success callback function parameters: Object res。
Properties Type Description bytesWritten number The number of bytes actually written to the file (note that the number of bytes written is not necessarily the same as the number of string characters written) Sample code:
const fs = wx.getFileSystemManager()
const fd = fs.openSync({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
flag: 'a+'
})
const res = fs.writeSync({
fd: fd,
data: 'some text'
})
console.log(res.bytesWritten).writeFile
TIP
The API usage is as follows: FileSystemManager.writeFile(Object object)
Functional description: Write the file
Parameters and descriptions: Object object。
Properties Type Default value Required Description filePath string - Yes The file path to be written data string/ArrayBuffer - Yes The text or binary data to be written encoding string utf-8 No Specify the character encoding for writing to the file. success Function - No Callback function for successful interface call fail Function - No Callback function for failed interface call complete Function - No Callback function for interface call completion (executed regardless of success or failure) Legal values
Value Description ascii - base64 - binary - hex - ucs2/ucs-2/utf16le/utf-16le Read in little endian utf-8/utf8 - latin1 - object.fail callback function parameter: Object res。
Properties Type Description errMsg string Error message Legal values
Value Description fail no such file or directory, open ${ filePath}the directory where the specified filePath is located does not exist fail permission denied, open ${ dirPath}The specified filePath path does not have write permission Sample code:
const fs = wx.getFileSystemManager()
fs.writeFile({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
data: 'some text or arrayBuffer',
encoding: 'utf8',
success(res) {
console.log(res)
},
fail(res) {
console.error(res)
}
})
//
try {
const res = fs.writeFileSync(
`${wx.env.USER_DATA_PATH}/hello.txt`,
'some text or arrayBuffer',
'utf8'
)
console.log(res)
} catch(e) {
console.error(e)
}.writeFileSync
TIP
The API usage is as follows: FileSystemManager.writeFileSync(string filePath, string|ArrayBuffer data, string encoding)
Functional description: FileSystemManager.writeFile The synchronous version
Parameters and descriptions:
- string filePath：The file path to be written
- string|ArrayBuffer data：The text or binary data to be written
- string encoding：Specify the character encoding for writing to the file.
Legal values
Value Description ascii - base64 (Note that when selecting base64 encoding, data only needs to pass the base64 content itself, and do not pass the Data URI prefix, otherwise the fail base64 encode error error will be reported. For example, pass aGVsbG8= instead of data:image/png;base64,aGVsbG8= ) - binary - hex - ucs2/ucs-2/utf16le/utf-16le Read in little endian utf-8/utf8 - latin1 - Sample code:
const fs = wx.getFileSystemManager()
fs.writeFile({
filePath: `${wx.env.USER_DATA_PATH}/hello.txt`,
data: 'some text or arrayBuffer',
encoding: 'utf8',
success(res) {
console.log(res)
},
fail(res) {
console.error(res)
}
})
try {
const res = fs.writeFileSync(
`${wx.env.USER_DATA_PATH}/hello.txt`,
'some text or arrayBuffer',
'utf8'
)
console.log(res)
} catch(e) {
console.error(e)
}Error code
TIP
Unless otherwise specified, the error codes are subject to the following table
| Error code | Error message | Description |
|---|---|---|
| 1300001 | operation not permitted | The operation is not allowed (for example, filePath expects to pass a file but actually passes a directory) |
| 1300002 | no such file or directory ${path} | The file/directory does not exist, or the parent directory of the target file path does not exist |
| 1300005 | Input/output error | The input and output streams are not available |
| 1300009 | bad file descriptor | Invalid file descriptor |
| 1300013 | permission denied | Permission error, the file is read-only or write-only |
| 1300014 | Path permission denied | The passed path has no permissions |
| 1300020 | not a directory | The dirPath specified path is not a directory, which is common when the parent path of the specified write path is a file |
| 1300021 | Is a directory | The specified path is a directory |
| 1300022 | Invalid argument | Invalid parameters, you can check whether length or offset is out of bounds |
| 1300036 | File name too long | The file name is too long |
| 1300066 | directory not empty | The directory is not empty |
| 1300201 | system error | The system interface call failed |
| 1300202 | the maximum size of the file storage limit is exceeded | Insufficient storage space, or the file size exceeds the upper limit (upper limit 100M) |
| 1300203 | base64 encode error | Character encoding conversion failed (for example, base64 format error) |
| 1300300 | sdcard not mounted | android sdcard mount failed |
| 1300301 | unable to open as fileType | Unable to open file with fileType |
| 1301000 | permission denied, cannot access file path | Destination path has no access rights (usr directory) |
| 1301002 | data to write is empty | Write data is empty |
| 1301003 | illegal operation on a directory | This operation cannot be performed on a directory (for example, the specified filePath is an existing directory) |
| 1301004 | illegal operation on a package directory | This operation cannot be performed on a code package directory |
| 1301005 | file already exists ${dirPath} | There is already a file or directory with the same name |
| 1301006 | value of length is out of range | The length passed in is illegal |
| 1301007 | value of offset is out of range | The offset passed in is illegal |
| 1301009 | value of position is out of range | Position value is out of bounds |
| 1301100 | store directory is empty | Store directory is empty |
| 1301102 | unzip open file fail | Compressed file opening failed |
| 1301103 | unzip entry fail | Single file decompression failed |
| 1301104 | unzip fail | Decompression failed |
| 1301111 | brotli decompress fail | Brotli decompression failed (for example, the specified compressionAlgorithm does not match the actual compression format of the file) |
| 1301112 | tempFilePath file not exist | The specified tempFilePath cannot find the file |
| 1302001 | fail permission denied | The specified fd path has no read permission/no write permission |
| 1302002 | exceed max concurrent fd limit | The number of fds has reached the upper limit |
| 1302003 | invalid flag | Invalid flag |
| 1302004 | permission denied when open using flag | Cannot use the flag flag to open the file |
| 1302005 | array buffer does not exist | ArrayBuffer is not passed in |
| 1302100 | array buffer is readonly | ArrayBuffer is read-only |
Stats
Object describing the file status
Properties
- number mode：File type and access permissions, corresponding to POSIX stat.st_mode
- number size：File size, unit: B, corresponding to POSIX stat.st_size
- number lastAccessedTime：The time when the file was last accessed or executed, UNIX timestamp, corresponding to POSIX stat.st_atime
- number lastModifiedTime：The time when the file was last modified, UNIX timestamp, corresponding to POSIX stat.st_mtime
Method set
.isDirectory
TIP
The API usage is as follows: boolean Stats.isDirectory()
- Functional description: Determine whether the current file is a directory
- Return value: boolean，Indicates whether the current file is a directory
.isFile
TIP
The API usage is as follows: boolean Stats.isFile()
- Functional description: Determine whether the current file is a regular file
- Return value: boolean，Indicates whether the current file is a regular file
ReadResult
- Functional description: File reading results. Through FileSystemManager.readSync Interface returns
- Properties
- number bytesRead，The actual number of bytes read
- ArrayBuffer arrayBuffer，The object of the buffer area written, that is, the arrayBuffer of the interface input parameter
WriteResult
- Functional description: File reading results. Through FileSystemManager.writeSync Interface returns
- Properties number bytesWritten，The number of bytes actually written to the file (note that the number of bytes written is not necessarily the same as the number of string characters written)