DriveApp

Create a new Drive file

function createFileOnDrive(name, content) {
  // Create an HTML file with the name and content provided
  DriveApp.createFile(name, content, MimeType.HTML);
}

Get a file from Drive

function getFileFromDrive(name) {
  const files = DriveApp.getFilesByName(name);
  if (files.hasNext()) {
    return files.next();
  } else {
    console.log(`No file found with name ${name}.`);
  }
}

List of files on a user's Drive

function listAllFiles() {
  // Log the name of every file in the user's Drive.
  const files = DriveApp.getFiles();
  for (const file of files) {
    console.log(file.getName());
  }
}

List of files in a folder

function listAllFilesInFolder(folderId) {
  // Log the name of every file in the folder.
  const files = DriveApp.getFolderById(folderId).getFiles();
  for (const file of files) {
    console.log(file.getName());
  }
}