DirectoryEntrySync

非标
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.

DirectoryEntrySync interface of the 文件系统 API represents a directory in a file system. It includes methods for creating, reading, looking up, and recursively removing files in a directory.

This interface has been abandonned: it was on a standard track and it proves not a good idea. Do not use it anymore.

About this document

This document was last updated on March 2, 2012 and follows the W3C Specifications (Working Draft) drafted on April 19, 2011.

This specification is pretty much abandoned, having failed to reach any substantial traction.

基本概念

If you want to create subdirectories, you have to create each child directory in sequence. If you try to create a directory using a full path that includes parent directories that do not exist yet, you get an error. So create the hierarchy by recursively adding a new path after creating the parent directory.

范例

getFile() method returns a FileEntrySync , which represents a file in the file system.  The following creates an empty file called seekrits.txt in the root directory.

var fileEntry = fs.root.getFile('seekrits.txt', {create: true});
					

getDirectory() method returns a DirectoryEntrySync , which represents a file in the file system. The following creates a new directory called superseekrit in the root directory.

var dirEntry = fs.root.getDirectory('superseekrit', {create: true});
					

Method overview

DirectoryReaderSync createReader () raises ( FileException );
FileEntrySync getFile (in DOMString path , in optional Flags options ) raises ( FileException );
DirectoryEntrySync getDirectory (in DOMString path, in optional Flags options ) raises ( FileException );
void removeRecursively () raises ( FileException );

方法

createReader()

创建新的 DirectoryReaderSync to read entries from this directory.

DirectoryReaderSync createReader (
) raises (FileException);
					
返回
DirectoryReaderSync
Represents a directory in a file system.
Parameter

None

异常

This method can raise a FileException with the following codes:

Exception 描述
NOT_FOUND_ERR The directory does not exist.
SECURITY_ERR The browser determined that it was not safe to look up the metadata. [ todo: Explain why ]

getFile()

Depending on how you've set the options parameter, the method either creates a file or looks up an existing file.

void getFile (
  in DOMString path, in optional Flags options
) raises (FileException);
					
Parameter
path
Either an absolute path or a relative path from the directory to the file to be looked up or created. You cannot create a file whose immediate parent does not exist. Create the parent directory first.
options
An object literal describing the behavior of the method. If the file does not exist, it is created.
Object literal Condition 结果
create: true
exclusive: true
Path already exists An error is thrown.
create: true
exclusive: false
Path doesn't exist and no other error occurs A file is created. If a file already exists, no error is thrown.
create: false
( exclusive is ignored)
Path exists The file is returned.
create: false
( exclusive is ignored)
Path doesn't exist An error is thrown.
create: false
( exclusive is ignored)
Path exists, but is a directory An error is thrown.
返回
FileEntrySync
Represents a file in a file system.
异常

This method can raise a FileException with the following codes:

Exception 描述
ENCODING_ERR The path supplied is invalid.
NOT_FOUND_ERR The path was structurally correct, but refers to a resource that does not exist.
NO_MODIFICATION_ALLOWED_ERR This is a permission issue. The target directory or file is not writable.
PATH_EXISTS_ERR The file already exists. You cannot create another one with the same path.
QUOTA_EXCEEDED_ERROR The operation would cause the application to exceed its storage quota.
SECURITY_ERR The application does not have permission to access the element referred to by path. [ todo: Explain why ]
TYPE_MISMATCH_ERR The path supplied exists, but it is not a directory.

getDirectory()

Creates or looks up a directory. The method is similar to getFile() with DirectoryEntrySync being passed.

void getDirectory (
  in DOMString path, in optional Flags options
) raises (FileException);
					
Parameter
path
Either an absolute path or a relative path from the directory to the file to be looked up or created. You cannot create a file whose immediate parent does not exist. Create the parent directory first.
options
An object literal describing the behavior of the method if the file does not exist.
Object literal Condition 结果
create: true
exclusive: true
Path already exists An error is thrown.
create: true
exclusive: false
Path doesn't exist and no other error occurs A directory is created. If a file already exists, no error is thrown.
create: false
( exclusive is ignored)
Path exists The directory is returned.
create: false
( exclusive is ignored)
Path doesn't exist An error is thrown.
create: false
( exclusive is ignored)
Path exists, but is a directory An error is thrown.
返回
DirectoryEntrySync
Represents a directory in a file system.
异常

This method can raise a FileException with the following codes:

Exception 描述
ENCODING_ERR The path supplied is invalid.
NOT_FOUND_ERR The path was structurally correct, but refers to a resource that does not exist.
NO_MODIFICATION_ALLOWED_ERR This is a permission issue. The target directory or file is not writable.
PATH_EXISTS_ERR The file already exists. You cannot create another one with the same path.
QUOTA_EXCEEDED_ERROR The operation would cause the application to exceed its storage quota.
SECURITY_ERR The application does not have permission to access the element referred to by path. [ todo: Explain why ]
TYPE_MISMATCH_ERR The path supplied exists, but it is not a directory.

removeRecursively()

Deletes a directory and all of its contents. You cannot delete the root directory of a file system.

If you delete a directory that contains a file that cannot be removed or if an error occurs while the deletion is in progress, some of the contents might not be deleted. Catch these cases with error callbacks and retry the deletion.

void removeRecursively (
)  raises (FileException);
					
Parameter

None

返回

void

异常

This method can raise a FileException with the following codes:

Exception 描述
NOT_FOUND_ERR The target directory does not exist.
INVALID_STATE_ERR This directory is not longer valid for some reason other than being deleted.

[todo: Explain more ]

NO_MODIFICATION_ALLOWED_ERR One of the following is not writable: the directory, its parent directory, and some of the content in the directory.
SECURITY_ERR The application does not have permission to access the target directory, its parent, or some of its contents.

浏览器兼容性

更新 GitHub 上的兼容性数据
Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
DirectoryEntrySync
非标
Chrome 13
Prefixed
13
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Edge 79
Prefixed
79
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Firefox 不支持 No IE 不支持 No Opera 不支持 No Safari 不支持 No WebView Android 37
Prefixed
37
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Chrome Android 18
Prefixed
18
Prefixed
Prefixed Implemented with the vendor prefix: webkit
Firefox Android 不支持 No Opera Android 不支持 No Safari iOS 不支持 No Samsung Internet Android 1.0
Prefixed
1.0
Prefixed
Prefixed Implemented with the vendor prefix: webkit

图例

完整支持
完整支持
不支持
不支持
非标。预期跨浏览器支持较差。
要求使用供应商前缀或不同名称。
要求使用供应商前缀或不同名称。

另请参阅

Specification: File API: Directories and System Specification WD

Reference: 文件系统 API

Introduction: Basic Concepts About the File System API