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FileSystemDirectoryHandle: keys() method

Baseline 2023

Newly available

Since ⁨March 2023⁩, this feature works across the latest devices and browser versions. This feature might not work in older devices or browsers.

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

Note: This feature is available in Web Workers.

The keys() method of the FileSystemDirectoryHandle interface returns a new asynchronous iterator for the iteration of the key of the entries within the FileSystemDirectoryHandle on which this method is called.

Syntax

keys()

Parameters

None.

Return value

A new asynchronous iterator containing the keys of each entry within the FileSystemDirectoryHandle.

Exceptions

NotAllowedError DOMException: Thrown if the PermissionStatus.state for the handle is not 'granted' in read mode.
NotFoundError DOMException: Thrown if the current entry is not found.

Examples

Use the for await...of loop can simplify the iteration process.

const dirHandle = await window.showDirectoryPicker();

for await (const key of dirHandle.keys()) {
  console.log(key);
}

Specifications

Specification
File System> # api-filesystemdirectoryhandle-asynciterable>

Browser compatibility

	Desktop					Mobile
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet	WebView Android	WebView on iOS
`keys`	86	86	111	72	15.2	109	111	74	15.2	21.0	109	15.2