FileSystemEntry - Web APIs 编辑

Non-standard

This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.

The FileSystemEntry interface of the File and Directory Entries API represents a single entry in a file system. The entry can be a file or a directory (directories are represented by the DirectoryEntry interface). It includes methods for working with files—including copying, moving, removing, and reading files—as well as information about a file it points to—including the file name and its path from the root to the entry.

Because this is a non-standard API, whose specification is not currently on a standards track, it's important to keep in mind that not all browsers implement it, and those that do may implement only small portions of it. Check the Browser compatibility section for details.

Basic concepts

You don't create FileSystemEntry objects directly. Instead, you will receive an object based on this interface through other APIs. This interface serves as a base class for the FileSystemFileEntry and FileSystemDirectoryEntry interfaces, which provide features specific to file system entries representing files and directories, respectively.

The FileSystemEntry interface includes methods that you would expect for manipulating files and directories, but it also includes a convenient method for obtaining the URL of the entry: toURL(). It also introduces a new URL scheme: filesystem:.

You can use the filesystem: scheme on Google Chrome to see all the files and folders that are stored in the origin of your app. Just use filesystem: scheme for the root directory of the origin of the app. For example, if your app is in http://www.html5rocks.com, openfilesystem:http://www.html5rocks.com/temporary/ in a tab. Chrome shows a read-only list of all the files and folders stored the origin of your app.

Example

To see an example of how toURL() works, see the method description. The snippet below shows you how you can remove a file by name.

// Taking care of the browser-specific prefixes.
window.requestFileSystem  = window.requestFileSystem || window.webkitRequestFileSystem;

...

// Opening a file system with temporary storage
window.requestFileSystem(TEMPORARY, 1024*1024 /*1MB*/, function(fs) {
  fs.root.getFile('log.txt', {}, function(fileEntry) {

    fileEntry.remove(function() {
      console.log('File removed.');
    }, onError);

  }, onError);
}, onError); 

Properties

This interface provides the following properties.

filesystem Read only

A FileSystem object representing the file system in which the entry is located.

fullPath Read only

A USVString object which provides the full, absolute path from the file system's root to the entry; it can also be thought of as a path which is relative to the root directory, prepended with a "/" character.

isDirectory Read only

A Boolean which is true if the entry represents a directory; otherwise, it's false.

isFile Read only

A Boolean which is true if the entry represents a file. If it's not a file, this value is false.

name Read only

A USVString containing the name of the entry (the final part of the path, after the last "/" character).

Methods

This interface defines the following methods.

copyTo()

Copies the file or directory to a new location on the file system.

getMetadata()

Obtains metadata about the file, such as its modification date and size.

getParent()

Returns a FileSystemDirectoryEntry representing the entry's parent directory.

moveTo()

Moves the file or directory to a new location on the file system, or renames the file or directory.

remove()

Removes the specified file or directory. You can only remove directories which are empty.

toURL()

Creates and returns a URL which identifies the entry. This URL uses the URL scheme "filesystem:".

Specifications

This API has no official W3C or WHATWG specification.

Browser compatibility

BCD tables only load in the browser

See also

• File and Directory Entries API
• Introduction to the File System API
• FileSystemFileEntry and FileSystemDirectoryEntry are based on FileSystemEntry.