Window: showOpenFilePicker() method

The showOpenFilePicker() method of the Window interface shows a file picker that allows a user to select a file or multiple files and returns a handle for the file(s).

Syntax

showOpenFilePicker()
showOpenFilePicker(options)

Parameters

options Optional

An object containing options, which are as follows:

excludeAcceptAllOption Optional

A boolean value that defaults to false. By default the picker should include an option to not apply any file type filters (instigated with the type option below). Setting this option to true means that option is not available.

id Optional

By specifying an ID, the browser can remember different directories for different IDs. If the same ID is used for another picker, the picker opens in the same directory.

multiple Optional

A boolean value that defaults to false. When set to true multiple files may be selected.

startIn Optional

A FileSystemHandle or a well known directory ("desktop", "documents", "downloads", "music", "pictures", or "videos") to open the dialog in.

types Optional

An Array of allowed file types to pick. Each item is an object with the following options:

description Optional

An optional description of the category of files types allowed. Defaults to an empty string.

accept

An Object with the keys set to the MIME type and the values an Array of file extensions (see below for an example).

Return value

A Promise whose fulfillment handler receives an Array of FileSystemFileHandle objects.

Exceptions

AbortError DOMException

Thrown if the user dismisses the prompt without making a selection, or if the user agent deems any selected files too sensitive or dangerous.

SecurityError DOMException

Thrown if the call was blocked by the same-origin policy or it was not called via a user interaction such as a button press.

TypeError

Thrown if accept types can't be processed, which may happen if:

• Any key string of the accept options of any item in types options can't parse a valid MIME type.
• Any value string(s) of the accept options of any item in types options is invalid, for example, if it does not start with . and if end with ., or if it contains any invalid code points and its length is more than 16.
• The types options is empty and the excludeAcceptAllOption options is true.

Security

Transient user activation is required. The user has to interact with the page or a UI element in order for this feature to work.

Examples

Here we set the options object for passing into the method. We'll allow a selection of image file types, with no option to allow for all files types, or multiple file selection.

const pickerOpts = {
 types: [
 {
 description: "Images",
 accept: {
 "image/*": [".png", ".gif", ".jpeg", ".jpg"],
 },
 },
 ],
 excludeAcceptAllOption: true,
 multiple: false,
};

Next we can create an asynchronous function which show the file picker and return the selected file.

// create a reference for our file handle
let fileHandle;
async function getFile() {
 // open file picker, destructure the one element returned array
 [fileHandle] = await window.showOpenFilePicker(pickerOpts);
 // run code with our fileHandle
}

Specifications

Browser compatibility

See also

• File System API
• The File System Access API: simplifying access to local files