Read files in JavaScript

                                    fetch('file.txt')
  .then(response => response.text())
  .then(text => console.log(text))
  // outputs the content of the text file

                                    function readImage(file) {  //function readImage(file) {
  // Check if the file is an image.
  if (file.type && !file.type.startsWith('image/')) {
    console.log('File is not an image.', file.type, file);
    return;
  }

  const reader = new FileReader();
  reader.addEventListener('load', (event) => {
    img.src = event.target.result;
  });
  reader.readAsDataURL(file);
} Check if the file is an image.  if (file.type && !file.type.startsWith('image/')) {    console.log('File is not an image.', file.type, file);    return;  }  const reader = new FileReader();  reader.addEventListener('load', (event) => {    img.src = event.target.result;  });  reader.readAsDataURL(file);}