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).

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

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).

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

AbortError DOMException

An AbortError is thrown if a user dismisses the prompt without making a selection or if a file selected is deemed too sensitive or dangerous to be exposed to the website.

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.

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

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
}

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