The FileSystemHandle
interface of the File System Access API
is an object which represents a file or directory entry. Multiple handles can represent the same entry. For the most part you do not work with FileSystemHandle
directly but rather its child interfaces FileSystemFileHandle
and FileSystemDirectoryHandle
.
Below is a list of interfaces based on the FileSystemHandle interface.
-
FileSystemFileHandle
-
Represents a handle to a file entry.
-
FileSystemDirectoryHandle
-
Provides a handle to a directory entry.
The below code allows the user to choose a file from the file picker and then tests to see whether the handle returned is a file or directory
let fileHandle;
async function getFile() {
[fileHandle] = await window.showOpenFilePicker();
if (fileHandle.kind === 'file') {
} else if (fileHandle.kind === 'directory')
}
}
The following asynchronous function returns true if user has granted read or readwrite permissions to the file handle. Permission is requested if not.
async function verifyPermission(fileHandle, withWrite) {
const opts = {};
if (withWrite) {
opts.mode = 'readwrite';
}
if (await fileHandle.queryPermission(opts) === 'granted') {
return true;
}
if (await fileHandle.requestPermission(opts) === 'granted') {
return true;
}
return false;
}
The following function compares a single entry with an array of entries, and returns a new array with any matching entries removed.
function removeMatches(fileEntry, entriesArr) {
let newArr = entriesArr.filter( entry => !fileEntry.isSameEntry(entry) )
return newArr;
}