API

async function getFile() {
  // 
  const [fileHandle] = await window.showOpenFilePicker();
  const file = await fileHandle.getFile();
  return file;
}

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

async function getTheFile() {
  // 
  const [fileHandle] = await window.showOpenFilePicker(pickerOpts);

  // 
  const fileData = await fileHandle.getFile();
}

const dirName = "directoryToGetName";

// 'currentDirHandle' 
const subDir = await currentDirHandle.getDirectoryHandle(dirName, {
  create: true,
});

async function returnPathDirectories(directoryHandle) {
  // 
  const [handle] = await self.showOpenFilePicker();
  if (!handle) {
    // 
    return;
  }

  // 
  const relativePaths = await directoryHandle.resolve(handle);

  if (relativePaths === null) {
    // 
  } else {
    // relativePaths 

    for (const name of relativePaths) {
      // 
      console.log(name);
    }
  }
}

async function saveFile() {
  // 
  const newHandle = await window.showSaveFilePicker();

  //  FileSystemWritableFileStream 
  const writableStream = await newHandle.createWritable();

  // 
  await writableStream.write(imgBlob);

  // 
  await writableStream.close();
}

//  ()
writableStream.write(data);

// 
writableStream.write({ type: "write", position, data });

// 
writableStream.write({ type: "seek", position });

//  size 
writableStream.write({ type: "truncate", size });

onmessage = async (e) => {
  // 
  const message = e.data;

  // OPFS  draft 
  const root = await navigator.storage.getDirectory();
  const draftHandle = await root.getFileHandle("draft.txt", { create: true });
  // 
  const accessHandle = await draftHandle.createSyncAccessHandle();

  // 
  const fileSize = accessHandle.getSize();
  // 
  const buffer = new DataView(new ArrayBuffer(fileSize));
  const readBuffer = accessHandle.read(buffer, { at: 0 });

  // 
  const encoder = new TextEncoder();
  const encodedMessage = encoder.encode(message);
  const writeBuffer = accessHandle.write(encodedMessage, { at: readBuffer });

  // 
  accessHandle.flush();

  //  FileSystemSyncAccessHandle 
  accessHandle.close();
};