FileSystemFlags

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特性
规范
浏览器兼容性
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这是实验性技术
检查浏览器兼容性表格要小心谨慎在生产中使用这之前。

FileSystemFlags dictionary defines a set of values which are used when specifying option flags when calling certain methods in the 文件和目录条目 API . Methods which accept an options parameter of this type may specify zero or more of these flags as fields in an object, like this:

dataDirectoryEntry.getDirectory("Workspace", { create: true }, function(entry) {
});

Here, we see that the create property is provided, with a value of true , indicating that the directory should be created if it's not already there.

Note that these option flags currently don't have any useful meaning when used in the scope of Web content, where security precautions prevent the creation of new files or the replacement of existing ones.

特性

create 可选: 若此特性为 true , and the requested file or directory doesn't exist, the user agent should create it. The default is false . The parent directory must already exist.
exclusive 可选: 若 true ，和 create option is also true , the file must not exist prior to issuing the call. Instead, it must be possible for it to be created newly at call time. The default is false .

Values and results

The table below describes the result of each possible combination of these flags depending on whether or not the target file or directory path already exists.

Option values		File/directory condition	结果
`create`	`exclusive`	File/directory condition	结果
`false`	n/a ^[1]	Path exists and matches the desired type (depending on whether the function called is `getFile()` or `getDirectory()`	`successCallback` is called with a `FileSystemFileEntry` if `getFile()` was called or a `FileSystemDirectoryEntry` if `getDirectory()` 被调用。
`false`	n/a ^[1]	Path exists but doesn't match the desired type	`errorCallback` is called with an appropriate error code (if the callback was provided).
`true`	`false`	Path exists	The existing file or directory is removed and replaced with a new one, then the `successCallback` is called with a `FileSystemFileEntry` 或 `FileSystemDirectoryEntry` , as appropriate.
`true`	`false`	Path doesn't exist	The file or directory is created, then a `FileSystemFileEntry` 或 `FileSystemDirectoryEntry` 被传递给 `successCallback` , as appropriate.
`true`	`true`	Path exists	`errorCallback` is called with an appropriate error, such as `FileError.PATH_EXISTS_ERR` .
`true`	`true`	Path doesn't exist	The file or directory is created, then a `FileSystemFileEntry` 或 `FileSystemDirectoryEntry` 被传递给 `successCallback` , as appropriate.

[1] When create is false ，值对于 exclusive is irrelevant and ignored.

规范

规范	状态	注释
文件和目录条目 API The definition of 'FileSystemFlags' in that specification.	草案	最初的规范。

浏览器兼容性

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request. 更新 GitHub 上的兼容性数据

	桌面						移动
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`FileSystemFlags`	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 50	IE No	Opera No	Safari No	WebView Android Yes Prefixed Yes Prefixed Prefixed Implemented with the vendor prefix: webkit	Chrome Android Yes Prefixed Yes Prefixed Prefixed Implemented with the vendor prefix: webkit	Firefox Android 50	Opera Android No	Safari iOS No	Samsung Internet Android Yes Prefixed Yes Prefixed Prefixed Implemented with the vendor prefix: webkit
`create`	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 部分支持 50 部分支持 50 For security reasons, Firefox does not support creating files. This option has no effect.	IE No	Opera No	Safari No	WebView Android Yes Prefixed Yes Prefixed Prefixed Implemented with the vendor prefix: webkit	Chrome Android Yes Prefixed Yes Prefixed Prefixed Implemented with the vendor prefix: webkit	Firefox Android 部分支持 50 部分支持 50 For security reasons, Firefox does not support creating files. This option has no effect.	Opera Android No	Safari iOS No	Samsung Internet Android Yes Prefixed Yes Prefixed Prefixed Implemented with the vendor prefix: webkit
`exclusive`	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 部分支持 50 部分支持 50 For security reasons, Firefox does not support creating files. This option has no effect.	IE No	Opera No	Safari No	WebView Android Yes Prefixed Yes Prefixed Prefixed Implemented with the vendor prefix: webkit	Chrome Android Yes Prefixed Yes Prefixed Prefixed Implemented with the vendor prefix: webkit	Firefox Android 部分支持 50 部分支持 50 For security reasons, Firefox does not support creating files. This option has no effect.	Opera Android No	Safari iOS No	Samsung Internet Android Yes Prefixed Yes Prefixed Prefixed Implemented with the vendor prefix: webkit

图例

完整支持
部分支持
不支持
实验。期望将来行为有所改变。

要求使用供应商前缀或不同名称。

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元数据

最后修改： Dec 25, 2019

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特性

Values and results

规范

浏览器兼容性

图例

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