This is documentation for the next SDK version. For up-to-date documentation, see the latest version (SDK 53).

Expo FileSystem

A library that provides access to the local file system on the device.

Android

iOS

tvOS

expo-file-system provides access to the file system stored locally on the device. It can also download files from the network.

Installation

Terminal

- npx expo install expo-file-system

If you are installing this in an existing React Native app, make sure to install expo in your project.

Usage

Writing and reading text files

example.ts

import { File, Paths } from 'expo-file-system';

try {
  const file = new File(Paths.cache, 'example.txt');
  file.create(); // can throw an error if the file already exists or no permission to create it
  file.write('Hello, world!');
  console.log(file.text()); // Hello, world!
} catch (error) {
  console.error(error);
}

Downloading files

Using downloadFileAsync:

example.ts

import { Directory, File, Paths } from 'expo-file-system';

const url = 'https://pdfobject.com/pdf/sample.pdf';
const destination = new Directory(Paths.cache, 'pdfs');
try {
  destination.create();
  const output = await File.downloadFileAsync(url, destination);
  console.log(output.exists); // true
  console.log(output.uri); // path to the downloaded file, e.g. '${cacheDirectory}/pdfs/sample.pdf'
} catch (error) {
  console.error(error);
}

Or using expo/fetch:

example.ts

import { fetch } from 'expo/fetch';
import { File } from 'expo-file-system';

const url = 'https://pdfobject.com/pdf/sample.pdf';
const response = await fetch(url);
const src = new File(testDirectory, 'file.pdf');
src.write(await response.bytes());

Uploading files using `expo/fetch`

You can upload files as blobs directly with fetch built into the Expo package:

example.ts

import { fetch } from 'expo/fetch';
import { File } from 'expo-file-system';

const src = new File(testDirectory, 'file.txt');
file.write('Hello, world!');
const blob = src.blob();

const response = await fetch('https://example.com', {
  method: 'POST',
  body: blob,
});

Or using the FormData constructor:

example.ts

import { fetch } from 'expo/fetch';

const src = new File(testDirectory, 'file.txt');
file.write('Hello, world!');
const blob = src.blob();

const formData = new FormData();
formData.append('data', blob);

const response = await fetch('https://example.com', {
  method: 'POST',
  body: formData,
});

Moving and copying files

example.ts

import { Directory, File, Paths } from 'expo-file-system';

try {
  const file = new File(Paths.document, 'example.txt');
  file.create();
  console.log(file.uri); // '${documentDirectory}/example.txt'
  file.move(Paths.cache);
  console.log(file.uri); // '${cacheDirectory}/example.txt'
  file.move(new Directory(Paths.cache, 'newFolder'));
  console.log(file.uri); // '${cacheDirectory}/newFolder/example.txt'
} catch (error) {
  console.error(error);
}

Using legacy FileSystem API

example.ts

import * as FileSystem from 'expo-file-system/legacy';
import { File, Paths } from 'expo-file-system';

try {
  const file = new File(Paths.cache, 'example.txt');
  const content = await FileSystem.readAsStringAsync(file.uri);
  console.log(content);
} catch (error) {
  console.error(error);
}

Listing directory contents recursively

example.ts

import { Directory, Paths } from 'expo-file-system';

function printDirectory(directory: Directory, indent: number = 0) {
  console.log(`${' '.repeat(indent)} + ${directory.name}`);
  const contents = directory.list();
  for (const item of contents) {
    if (item instanceof Directory) {
      printDirectory(item, indent + 2);
    } else {
      console.log(`${' '.repeat(indent + 2)} - ${item.name} (${item.size} bytes)`);
    }
  }
}

try {
  printDirectory(new Directory(Paths.cache));
} catch (error) {
  console.error(error);
}

API

Constants

`FileSystem.bundleDirectory`

Android

iOS

tvOS

Type: null | string

URI to the directory where assets bundled with the application are stored.

`FileSystem.cacheDirectory`

Android

iOS

tvOS

Type: null | string

file:// URI pointing to the directory where temporary files used by this app will be stored. Files stored here may be automatically deleted by the system when low on storage. Example uses are for downloaded or generated files that the app just needs for one-time usage.

`FileSystem.documentDirectory`

Android

iOS

tvOS

Type: null | string

file:// URI pointing to the directory where user documents for this app will be stored. Files stored here will remain until explicitly deleted by the app. Ends with a trailing /. Example uses are for files the user saves that they expect to see again.

Classes

`DownloadResumable`

Android

iOS

tvOS

Type: Class extends FileSystemCancellableNetworkTask<DownloadProgressData>

DownloadResumable Properties

`fileUri`

Android

iOS

tvOS

Type: string

DownloadResumable Methods

`cancelAsync()`

Android

iOS

tvOS

Returns:

Promise<void>

`downloadAsync()`

Android

iOS

tvOS

Download the contents at a remote URI to a file in the app's file system.

Returns:

Promise<undefined | FileSystemDownloadResult>

Returns a Promise that resolves to FileSystemDownloadResult object, or to undefined when task was cancelled.

`pauseAsync()`

Android

iOS

tvOS

Pause the current download operation. resumeData is added to the DownloadResumable object after a successful pause operation. Returns an object that can be saved with AsyncStorage for future retrieval (the same object that is returned from calling FileSystem.DownloadResumable.savable()).

Returns:

Promise<DownloadPauseState>

Returns a Promise that resolves to DownloadPauseState object.

`resumeAsync()`

Android

iOS

tvOS

Resume a paused download operation.

Returns:

Promise<undefined | FileSystemDownloadResult>

Returns a Promise that resolves to FileSystemDownloadResult object, or to undefined when task was cancelled.

`savable()`

Android

iOS

tvOS

Method to get the object which can be saved with AsyncStorage for future retrieval.

Returns:

DownloadPauseState

Returns object in shape of DownloadPauseState type.

`FileSystemCancellableNetworkTask`

Android

iOS

tvOS

FileSystemCancellableNetworkTask Methods

`cancelAsync()`

Android

iOS

tvOS

Returns:

Promise<void>

`UploadTask`

Android

iOS

tvOS

Type: Class extends FileSystemCancellableNetworkTask<UploadProgressData>

UploadTask Methods

`cancelAsync()`

Android

iOS

tvOS

Returns:

Promise<void>

`uploadAsync()`

Android

iOS

tvOS

Returns:

Promise<undefined | FileSystemUploadResult>

Methods

`FileSystem.copyAsync(options)`

Android

iOS

tvOS

Parameter	Type	Description
options	`RelocatingOptions`	A map of move options represented by `RelocatingOptions` type.

Create a copy of a file or directory. Directories are recursively copied with all of their contents. It can be also used to copy content shared by other apps to local filesystem.

Returns:

Promise<void>

`FileSystem.createDownloadResumable(uri, fileUri, options, callback, resumeData)`

Android

iOS

tvOS

Parameter	Type	Description
uri	`string`	The remote URI to download from.
fileUri	`string`	The local URI of the file to download to. If there is no file at this URI, a new one is created. If there is a file at this URI, its contents are replaced. The directory for the file must exist.
options(optional)	`DownloadOptions`	A map of download options represented by `DownloadOptions` type.
callback(optional)	`FileSystemNetworkTaskProgressCallback<DownloadProgressData>`	This function is called on each data write to update the download progress. Note: When the app has been moved to the background, this callback won't be fired until it's moved to the foreground.
resumeData(optional)	`string`	The string which allows the api to resume a paused download. This is set on the `DownloadResumable` object automatically when a download is paused. When initializing a new `DownloadResumable` this should be `null`.

Create a DownloadResumable object which can start, pause, and resume a download of contents at a remote URI to a file in the app's file system.

Note: You need to call downloadAsync(), on a DownloadResumable instance to initiate the download. The DownloadResumable object has a callback that provides download progress updates. Downloads can be resumed across app restarts by using AsyncStorage to store the DownloadResumable.savable() object for later retrieval. The savable object contains the arguments required to initialize a new DownloadResumable object to resume the download after an app restart. The directory for a local file uri must exist prior to calling this function.

Returns:

DownloadResumable

`FileSystem.createUploadTask(url, fileUri, options, callback)`

Android

iOS

tvOS

Parameter	Type
url	`string`
fileUri	`string`
options(optional)	`FileSystemUploadOptions`
callback(optional)	`FileSystemNetworkTaskProgressCallback<UploadProgressData>`

Returns:

UploadTask

`FileSystem.deleteAsync(fileUri, options)`

Android

iOS

tvOS

Parameter	Type	Description
fileUri	`string`	`file://` or SAF URI to the file or directory.
options(optional)	`DeletingOptions`	A map of write options represented by `DeletingOptions` type. Default:`{}`

Delete a file or directory. If the URI points to a directory, the directory and all its contents are recursively deleted.

Returns:

Promise<void>

`FileSystem.deleteLegacyDocumentDirectoryAndroid()`

Android

iOS

tvOS

Returns:

Promise<void>

`FileSystem.downloadAsync(uri, fileUri, options)`

Android

iOS

tvOS

Parameter	Type	Description
uri	`string`	The remote URI to download from.
fileUri	`string`	The local URI of the file to download to. If there is no file at this URI, a new one is created. If there is a file at this URI, its contents are replaced. The directory for the file must exist.
options(optional)	`DownloadOptions`	A map of download options represented by `DownloadOptions` type. Default:`{}`

Download the contents at a remote URI to a file in the app's file system. The directory for a local file uri must exist prior to calling this function.

Returns:

Promise<FileSystemDownloadResult>

Returns a Promise that resolves to a FileSystemDownloadResult object.

Example

FileSystem.downloadAsync(
  'http://techslides.com/demos/sample-videos/small.mp4',
  FileSystem.documentDirectory + 'small.mp4'
)
  .then(({ uri }) => {
    console.log('Finished downloading to ', uri);
  })
  .catch(error => {
    console.error(error);
  });

`FileSystem.getContentUriAsync(fileUri)`

Android

Parameter	Type	Description
fileUri	`string`	The local URI of the file. If there is no file at this URI, an exception will be thrown.

Takes a file:// URI and converts it into content URI (content://) so that it can be accessed by other applications outside of Expo.

Returns:

Promise<string>

Returns a Promise that resolves to a string containing a content:// URI pointing to the file. The URI is the same as the fileUri input parameter but in a different format.

Example

FileSystem.getContentUriAsync(uri).then(cUri => {
  console.log(cUri);
  IntentLauncher.startActivityAsync('android.intent.action.VIEW', {
    data: cUri,
    flags: 1,
  });
});

`FileSystem.getFreeDiskStorageAsync()`

Android

iOS

tvOS

Gets the available internal disk storage size, in bytes. This returns the free space on the data partition that hosts all of the internal storage for all apps on the device.

Returns:

Promise<number>

Returns a Promise that resolves to the number of bytes available on the internal disk.

`FileSystem.getInfoAsync(fileUri, options)`

Android

iOS

tvOS

Parameter	Type	Description
fileUri	`string`	URI to the file or directory. See supported URI schemes.
options(optional)	`InfoOptions`	A map of options represented by `InfoOptions` type. Default:`{}`

Get metadata information about a file, directory or external content/asset.

Returns:

Promise<FileInfo>

A Promise that resolves to a FileInfo object. If no item exists at this URI, the returned Promise resolves to FileInfo object in form of { exists: false, isDirectory: false }.

`FileSystem.getTotalDiskCapacityAsync()`

Android

iOS

tvOS

Gets total internal disk storage size, in bytes. This is the total capacity of the data partition that hosts all the internal storage for all apps on the device.

Returns:

Promise<number>

Returns a Promise that resolves to a number that specifies the total internal disk storage capacity in bytes.

`FileSystem.makeDirectoryAsync(fileUri, options)`

Android

iOS

tvOS

Parameter	Type	Description
fileUri	`string`	`file://` URI to the new directory to create.
options(optional)	`MakeDirectoryOptions`	A map of create directory options represented by `MakeDirectoryOptions` type. Default:`{}`

Create a new empty directory.

Returns:

Promise<void>

`FileSystem.moveAsync(options)`

Android

iOS

tvOS

Parameter	Type	Description
options	`RelocatingOptions`	A map of move options represented by `RelocatingOptions` type.

Move a file or directory to a new location.

Returns:

Promise<void>

`FileSystem.readAsStringAsync(fileUri, options)`

Android

iOS

tvOS

Parameter	Type	Description
fileUri	`string`	`file://` or SAF URI to the file or directory.
options(optional)	`ReadingOptions`	A map of read options represented by `ReadingOptions` type. Default:`{}`

Read the entire contents of a file as a string. Binary will be returned in raw format, you will need to append data:image/png;base64, to use it as Base64.

Returns:

Promise<string>

A Promise that resolves to a string containing the entire contents of the file.

`FileSystem.readDirectoryAsync(fileUri)`

Android

iOS

tvOS

Parameter	Type	Description
fileUri	`string`	`file://` URI to the directory.

Enumerate the contents of a directory.

Returns:

Promise<string[]>

A Promise that resolves to an array of strings, each containing the name of a file or directory contained in the directory at fileUri.

`FileSystem.uploadAsync(url, fileUri, options)`

Android

iOS

tvOS

Parameter	Type	Description
url	`string`	The remote URL, where the file will be sent.
fileUri	`string`	The local URI of the file to send. The file must exist.
options(optional)	`FileSystemUploadOptions`	A map of download options represented by `FileSystemUploadOptions` type. Default:`{}`

Upload the contents of the file pointed by fileUri to the remote url.

Returns:

Promise<FileSystemUploadResult>

Returns a Promise that resolves to FileSystemUploadResult object.

Example

Client

import * as FileSystem from 'expo-file-system';

try {
  const response = await FileSystem.uploadAsync(`http://192.168.0.1:1234/binary-upload`, fileUri, {
    fieldName: 'file',
    httpMethod: 'PATCH',
    uploadType: FileSystem.FileSystemUploadType.BINARY_CONTENT,
  });
  console.log(JSON.stringify(response, null, 4));
} catch (error) {
  console.log(error);
}

Server

Please refer to the "Server: Handling multipart requests" example - there is code for a simple Node.js server.

`FileSystem.writeAsStringAsync(fileUri, contents, options)`

Android

iOS

tvOS

Parameter	Type	Description
fileUri	`string`	`file://` or SAF URI to the file or directory. Note: when you're using SAF URI the file needs to exist. You can't create a new file.
contents	`string`	The string to replace the contents of the file with.
options(optional)	`WritingOptions`	A map of write options represented by `WritingOptions` type. Default:`{}`

Write the entire contents of a file as a string.

Returns:

Promise<void>

Namespaces

`StorageAccessFramework`

Android

The StorageAccessFramework is a namespace inside of the expo-file-system module, which encapsulates all functions which can be used with SAF URIs. You can read more about SAF in the Android documentation.

Example

Basic Usage

import { StorageAccessFramework } from 'expo-file-system';

// Requests permissions for external directory
const permissions = await StorageAccessFramework.requestDirectoryPermissionsAsync();

if (permissions.granted) {
  // Gets SAF URI from response
  const uri = permissions.directoryUri;

  // Gets all files inside of selected directory
  const files = await StorageAccessFramework.readDirectoryAsync(uri);
  alert(`Files inside ${uri}:\n\n${JSON.stringify(files)}`);
}

Migrating an album

import * as MediaLibrary from 'expo-media-library';
import * as FileSystem from 'expo-file-system';
const { StorageAccessFramework } = FileSystem;

async function migrateAlbum(albumName: string) {
  // Gets SAF URI to the album
  const albumUri = StorageAccessFramework.getUriForDirectoryInRoot(albumName);

  // Requests permissions
  const permissions = await StorageAccessFramework.requestDirectoryPermissionsAsync(albumUri);
  if (!permissions.granted) {
    return;
  }

  const permittedUri = permissions.directoryUri;
  // Checks if users selected the correct folder
  if (!permittedUri.includes(albumName)) {
    return;
  }

  const mediaLibraryPermissions = await MediaLibrary.requestPermissionsAsync();
  if (!mediaLibraryPermissions.granted) {
    return;
  }

  // Moves files from external storage to internal storage
  await StorageAccessFramework.moveAsync({
    from: permittedUri,
    to: FileSystem.documentDirectory!,
  });

  const outputDir = FileSystem.documentDirectory! + albumName;
  const migratedFiles = await FileSystem.readDirectoryAsync(outputDir);

  // Creates assets from local files
  const [newAlbumCreator, ...assets] = await Promise.all(
    migratedFiles.map<Promise<MediaLibrary.Asset>>(
      async fileName => await MediaLibrary.createAssetAsync(outputDir + '/' + fileName)
    )
  );

  // Album was empty
  if (!newAlbumCreator) {
    return;
  }

  // Creates a new album in the scoped directory
  const newAlbum = await MediaLibrary.createAlbumAsync(albumName, newAlbumCreator, false);
  if (assets.length) {
    await MediaLibrary.addAssetsToAlbumAsync(assets, newAlbum, false);
  }
}

StorageAccessFramework Methods

`copyAsync(options)`

Android

Parameter	Type	Description
options	`RelocatingOptions`	A map of move options represented by `RelocatingOptions` type.

Alias for copyAsync method.

Returns:

Promise<void>

`createFileAsync(parentUri, fileName, mimeType)`

Android

Parameter	Type	Description
parentUri	`string`	The SAF URI to the parent directory.
fileName	`string`	The name of new file without the extension.
mimeType	`string`	The MIME type of new file.

Creates a new empty file.

Returns:

Promise<string>

A Promise that resolves to a SAF URI to the created file.

`deleteAsync(fileUri, options)`

Android

Parameter	Type	Description
fileUri	`string`	`file://` or SAF URI to the file or directory.
options(optional)	`DeletingOptions`	A map of write options represented by `DeletingOptions` type. Default:`{}`

Alias for deleteAsync method.

Returns:

Promise<void>

`getUriForDirectoryInRoot(folderName)`

Android

Parameter	Type	Description
folderName	`string`	The name of the folder which is located in the Android root directory.

Gets a SAF URI pointing to a folder in the Android root directory. You can use this function to get URI for StorageAccessFramework.requestDirectoryPermissionsAsync() when you trying to migrate an album. In that case, the name of the album is the folder name.

Returns:

string

Returns a SAF URI to a folder.

`makeDirectoryAsync(parentUri, dirName)`

Android

Parameter	Type	Description
parentUri	`string`	The SAF URI to the parent directory.
dirName	`string`	The name of new directory.

Creates a new empty directory.

Returns:

Promise<string>

A Promise that resolves to a SAF URI to the created directory.

`moveAsync(options)`

Android

Parameter	Type	Description
options	`RelocatingOptions`	A map of move options represented by `RelocatingOptions` type.

Alias for moveAsync method.

Returns:

Promise<void>

`readAsStringAsync(fileUri, options)`

Android

Parameter	Type	Description
fileUri	`string`	`file://` or SAF URI to the file or directory.
options(optional)	`ReadingOptions`	A map of read options represented by `ReadingOptions` type. Default:`{}`

Alias for readAsStringAsync method.

Returns:

Promise<string>

A Promise that resolves to a string containing the entire contents of the file.

`readDirectoryAsync(dirUri)`

Android

Parameter	Type	Description
dirUri	`string`	SAF URI to the directory.

Enumerate the contents of a directory.

Returns:

Promise<string[]>

A Promise that resolves to an array of strings, each containing the full SAF URI of a file or directory contained in the directory at fileUri.

`requestDirectoryPermissionsAsync(initialFileUrl)`

Android 11+

Parameter	Type	Description
initialFileUrl(optional)	`null \| string`	The SAF URI of the directory that the file picker should display when it first loads. If URI is incorrect or points to a non-existing folder, it's ignored. Default:`null`

Allows users to select a specific directory, granting your app access to all of the files and sub-directories within that directory.

Returns:

Promise<FileSystemRequestDirectoryPermissionsResult>

Returns a Promise that resolves to FileSystemRequestDirectoryPermissionsResult object.

`writeAsStringAsync(fileUri, contents, options)`

Android

Parameter	Type	Description
fileUri	`string`	`file://` or SAF URI to the file or directory. Note: when you're using SAF URI the file needs to exist. You can't create a new file.
contents	`string`	The string to replace the contents of the file with.
options(optional)	`WritingOptions`	A map of write options represented by `WritingOptions` type. Default:`{}`

Alias for writeAsStringAsync method.

Returns:

Promise<void>

Types

`DeletingOptions`

Android

iOS

tvOS

Property	Type	Description
idempotent(optional)	`boolean`	If `true`, don't throw an error if there is no file or directory at this URI. Default:`false`

`DownloadOptions`

Android

iOS

tvOS

Property	Type	Description
cache(optional)	`boolean`	-
headers(optional)	`Record<string, string>`	An object containing all the HTTP header fields and their values for the download network request. The keys and values of the object are the header names and values respectively.
md5(optional)	`boolean`	If `true`, include the MD5 hash of the file in the returned object. Provided for convenience since it is common to check the integrity of a file immediately after downloading. Default:`false`
sessionType(optional)	`FileSystemSessionType`	Only for: iOS A session type. Determines if tasks can be handled in the background. On Android, sessions always work in the background and you can't change it. Default:`FileSystemSessionType.BACKGROUND`

`DownloadPauseState`

Android

iOS

tvOS

Property	Type	Description
fileUri	`string`	The local URI of the file to download to. If there is no file at this URI, a new one is created. If there is a file at this URI, its contents are replaced.
options	`DownloadOptions`	Object representing the file download options.
resumeData(optional)	`string`	The string which allows the API to resume a paused download.
url	`string`	The remote URI to download from.

Deprecated use FileSystemNetworkTaskProgressCallback<DownloadProgressData> instead.

`DownloadProgressCallback`

Android

iOS

tvOS

Type: FileSystemNetworkTaskProgressCallback<DownloadProgressData>

`DownloadProgressData`

Android

iOS

tvOS

Property	Type	Description
totalBytesExpectedToWrite	`number`	The total bytes expected to be written by the download operation. A value of `-1` means that the server did not return the `Content-Length` header and the total size is unknown. Without this header, you won't be able to track the download progress.
totalBytesWritten	`number`	The total bytes written by the download operation.

Deprecated Use FileSystemDownloadResult instead.

`DownloadResult`

Android

iOS

tvOS

Type: FileSystemDownloadResult

`FileInfo`

Android

iOS

tvOS

Type: object shaped as below:

Property	Type	Description
exists	`true`	Signifies that the requested file exist.
isDirectory	`boolean`	Boolean set to `true` if this is a directory and `false` if it is a file.
md5(optional)	`string`	Present if the `md5` option was truthy. Contains the MD5 hash of the file.
modificationTime	`number`	The last modification time of the file expressed in seconds since epoch.
size	`number`	The size of the file in bytes. If operating on a source such as an iCloud file, only present if the `size` option was truthy.
uri	`string`	A `file://` URI pointing to the file. This is the same as the `fileUri` input parameter.

Or object shaped as below:

Property	Type	Description
exists	`false`	-
isDirectory	`false`	-
uri	`string`	-

`FileSystemAcceptedUploadHttpMethod`

Android

iOS

tvOS

Literal Type: string

Acceptable values are: 'POST' | 'PUT' | 'PATCH'

`FileSystemDownloadResult`

Android

iOS

tvOS

Type: FileSystemHttpResult extended by:

Property	Type	Description
md5(optional)	`string`	Present if the `md5` option was truthy. Contains the MD5 hash of the file.
uri	`string`	A `file://` URI pointing to the file. This is the same as the `fileUri` input parameter.

`FileSystemHttpResult`

Android

iOS

tvOS

Property	Type	Description
headers	`Record<string, string>`	An object containing all the HTTP response header fields and their values for the download network request. The keys and values of the object are the header names and values respectively.
mimeType	`string \| null`	-
status	`number`	The HTTP response status code for the download network request.

`FileSystemNetworkTaskProgressCallback(data)`

Android

iOS

tvOS

Parameter	Type
data	`T`

Returns:

void

`FileSystemRequestDirectoryPermissionsResult`

Android

iOS

tvOS

Type: object shaped as below:

Property	Type	Description
granted	`false`	-

Or object shaped as below:

Property	Type	Description
directoryUri	`string`	The SAF URI to the user's selected directory. Available only if permissions were granted.
granted	`true`	-

`FileSystemUploadOptions`

Android

iOS

tvOS

Type: UploadOptionsBinary | UploadOptionsMultipart extended by:

Property	Type	Description
headers(optional)	`Record<string, string>`	An object containing all the HTTP header fields and their values for the upload network request. The keys and values of the object are the header names and values respectively.
httpMethod(optional)	`FileSystemAcceptedUploadHttpMethod`	The request method. Default:`FileSystemAcceptedUploadHttpMethod.POST`
sessionType(optional)	`FileSystemSessionType`	Only for: iOS A session type. Determines if tasks can be handled in the background. On Android, sessions always work in the background and you can't change it. Default:`FileSystemSessionType.BACKGROUND`

`FileSystemUploadResult`

Android

iOS

tvOS

Type: FileSystemHttpResult extended by:

Property	Type	Description
body	`string`	The body of the server response.

`InfoOptions`

Android

iOS

tvOS

Property	Type	Description
md5(optional)	`boolean`	Whether to return the MD5 hash of the file. Default:`false`
size(optional)	`boolean`	Explicitly specify that the file size should be included. For example, skipping this can prevent downloading the file if it's stored in iCloud. The size is always returned for `file://` locations.

`MakeDirectoryOptions`

Android

iOS

tvOS

Property	Type	Description
intermediates(optional)	`boolean`	If `true`, don't throw an error if there is no file or directory at this URI. Default:`false`

`ProgressEvent`

Android

iOS

tvOS

Property	Type	Description
data	`T`	-
uuid	`string`	-

`ReadingOptions`

Android

iOS

tvOS

Property	Type	Description
encoding(optional)	`EncodingType \| 'utf8' \| 'base64'`	The encoding format to use when reading the file. Default:`EncodingType.UTF8`
length(optional)	`number`	Optional number of bytes to read. This option is only used when `encoding: FileSystem.EncodingType.Base64` and `position` is defined.
position(optional)	`number`	Optional number of bytes to skip. This option is only used when `encoding: FileSystem.EncodingType.Base64` and `length` is defined.

`RelocatingOptions`

Android

iOS

tvOS

Property	Type	Description
from	`string`	URI or SAF URI to the asset, file, or directory. See supported URI schemes.
to	`string`	`file://` URI to the file or directory which should be its new location.

`UploadOptionsBinary`

Android

iOS

tvOS

Upload options when upload type is set to binary.

Property	Type	Description
uploadType(optional)	`FileSystemUploadType`	Upload type determines how the file will be sent to the server. Value will be `FileSystemUploadType.BINARY_CONTENT`.

`UploadOptionsMultipart`

Android

iOS

tvOS

Upload options when upload type is set to multipart.

Property	Type	Description
fieldName(optional)	`string`	The name of the field which will hold uploaded file. Defaults to the file name without an extension.
mimeType(optional)	`string`	The MIME type of the provided file. If not provided, the module will try to guess it based on the extension.
parameters(optional)	`Record<string, string>`	Additional form properties. They will be located in the request body.
uploadType	`FileSystemUploadType`	Upload type determines how the file will be sent to the server. Value will be `FileSystemUploadType.MULTIPART`.

`UploadProgressData`

Android

iOS

tvOS

Property	Type	Description
totalBytesExpectedToSend	`number`	The total bytes expected to be sent by the upload operation.
totalBytesSent	`number`	The total bytes sent by the upload operation.

`WritingOptions`

Android

iOS

tvOS

Property	Type	Description
encoding(optional)	`EncodingType \| 'utf8' \| 'base64'`	The encoding format to use when writing the file. Default:`FileSystem.EncodingType.UTF8`

Enums

`EncodingType`

Android

iOS

tvOS

These values can be used to define how file system data is read / written.

`Base64`

EncodingType.Base64 ＝ "base64"

Binary, radix-64 representation.

`UTF8`

EncodingType.UTF8 ＝ "utf8"

Standard encoding format.

`FileSystemSessionType`

iOS

These values can be used to define how sessions work on iOS.

`BACKGROUND`

FileSystemSessionType.BACKGROUND ＝ 0

Using this mode means that the downloading/uploading session on the native side will work even if the application is moved to background. If the task completes while the application is in background, the Promise will be either resolved immediately or (if the application execution has already been stopped) once the app is moved to foreground again.

Note: The background session doesn't fail if the server or your connection is down. Rather, it continues retrying until the task succeeds or is canceled manually.

`FOREGROUND`

FileSystemSessionType.FOREGROUND ＝ 1

Using this mode means that downloading/uploading session on the native side will be terminated once the application becomes inactive (e.g. when it goes to background). Bringing the application to foreground again would trigger Promise rejection.

`FileSystemUploadType`

Android

iOS

tvOS

`BINARY_CONTENT`

FileSystemUploadType.BINARY_CONTENT ＝ 0

The file will be sent as a request's body. The request can't contain additional data.

`MULTIPART`

FileSystemUploadType.MULTIPART ＝ 1

An RFC 2387-compliant request body. The provided file will be encoded into HTTP request. This request can contain additional data represented by UploadOptionsMultipart type.

Expo FileSystem

Installation

Usage

Writing and reading text files

Downloading files

Uploading files using expo/fetch

Moving and copying files

Using legacy FileSystem API

Listing directory contents recursively

API

Constants

FileSystem.bundleDirectory

FileSystem.cacheDirectory

FileSystem.documentDirectory

Classes

DownloadResumable

fileUri

cancelAsync()

downloadAsync()

pauseAsync()

resumeAsync()

savable()

FileSystemCancellableNetworkTask

cancelAsync()

UploadTask

cancelAsync()

uploadAsync()

Methods

FileSystem.copyAsync(options)

FileSystem.createDownloadResumable(uri, fileUri, options, callback, resumeData)

FileSystem.createUploadTask(url, fileUri, options, callback)

FileSystem.deleteAsync(fileUri, options)

FileSystem.deleteLegacyDocumentDirectoryAndroid()

FileSystem.downloadAsync(uri, fileUri, options)

FileSystem.getContentUriAsync(fileUri)

FileSystem.getFreeDiskStorageAsync()

FileSystem.getInfoAsync(fileUri, options)

FileSystem.getTotalDiskCapacityAsync()

FileSystem.makeDirectoryAsync(fileUri, options)

FileSystem.moveAsync(options)

FileSystem.readAsStringAsync(fileUri, options)

FileSystem.readDirectoryAsync(fileUri)

FileSystem.uploadAsync(url, fileUri, options)

FileSystem.writeAsStringAsync(fileUri, contents, options)

Namespaces

StorageAccessFramework

Basic Usage

Migrating an album

copyAsync(options)

createFileAsync(parentUri, fileName, mimeType)

deleteAsync(fileUri, options)

getUriForDirectoryInRoot(folderName)

makeDirectoryAsync(parentUri, dirName)

moveAsync(options)

readAsStringAsync(fileUri, options)

readDirectoryAsync(dirUri)

requestDirectoryPermissionsAsync(initialFileUrl)

writeAsStringAsync(fileUri, contents, options)

Types

DeletingOptions

DownloadOptions

DownloadPauseState

DownloadProgressCallback

DownloadProgressData

DownloadResult

FileInfo

FileSystemAcceptedUploadHttpMethod

FileSystemDownloadResult

FileSystemHttpResult

FileSystemNetworkTaskProgressCallback(data)

FileSystemRequestDirectoryPermissionsResult

FileSystemUploadOptions

FileSystemUploadResult

InfoOptions

MakeDirectoryOptions

ProgressEvent

ReadingOptions

RelocatingOptions

UploadOptionsBinary

UploadOptionsMultipart

Uploading files using `expo/fetch`

`FileSystem.bundleDirectory`

`FileSystem.cacheDirectory`

`FileSystem.documentDirectory`

`DownloadResumable`

`fileUri`

`cancelAsync()`

`downloadAsync()`

`pauseAsync()`

`resumeAsync()`

`savable()`

`FileSystemCancellableNetworkTask`

`cancelAsync()`

`UploadTask`

`cancelAsync()`

`uploadAsync()`

`FileSystem.copyAsync(options)`

`FileSystem.createDownloadResumable(uri, fileUri, options, callback, resumeData)`

`FileSystem.createUploadTask(url, fileUri, options, callback)`

`FileSystem.deleteAsync(fileUri, options)`

`FileSystem.deleteLegacyDocumentDirectoryAndroid()`

`FileSystem.downloadAsync(uri, fileUri, options)`

`FileSystem.getContentUriAsync(fileUri)`

`FileSystem.getFreeDiskStorageAsync()`

`FileSystem.getInfoAsync(fileUri, options)`

`FileSystem.getTotalDiskCapacityAsync()`

`FileSystem.makeDirectoryAsync(fileUri, options)`

`FileSystem.moveAsync(options)`

`FileSystem.readAsStringAsync(fileUri, options)`

`FileSystem.readDirectoryAsync(fileUri)`

`FileSystem.uploadAsync(url, fileUri, options)`

`FileSystem.writeAsStringAsync(fileUri, contents, options)`

`StorageAccessFramework`

`copyAsync(options)`

`createFileAsync(parentUri, fileName, mimeType)`

`deleteAsync(fileUri, options)`

`getUriForDirectoryInRoot(folderName)`

`makeDirectoryAsync(parentUri, dirName)`

`moveAsync(options)`

`readAsStringAsync(fileUri, options)`

`readDirectoryAsync(dirUri)`

`requestDirectoryPermissionsAsync(initialFileUrl)`

`writeAsStringAsync(fileUri, contents, options)`

`DeletingOptions`

`DownloadOptions`

`DownloadPauseState`

`DownloadProgressCallback`

`DownloadProgressData`

`DownloadResult`

`FileInfo`

`FileSystemAcceptedUploadHttpMethod`

`FileSystemDownloadResult`

`FileSystemHttpResult`

`FileSystemNetworkTaskProgressCallback(data)`

`FileSystemRequestDirectoryPermissionsResult`

`FileSystemUploadOptions`

`FileSystemUploadResult`

`InfoOptions`

`MakeDirectoryOptions`

`ProgressEvent`

`ReadingOptions`

`RelocatingOptions`

`UploadOptionsBinary`

`UploadOptionsMultipart`

`UploadProgressData`

`WritingOptions`

`EncodingType`

`Base64`

`UTF8`

`FileSystemSessionType`

`BACKGROUND`

`FOREGROUND`

`FileSystemUploadType`

`BINARY_CONTENT`

`MULTIPART`