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                <input type="file" id="files" name="files" />
<textarea id="base64" rows="5"></textarea>




                // Check for the File API support.
if (window.File && window.FileReader && window.FileList && window.Blob) {
  document.getElementById('files').addEventListener('change', handleFileSelect, false);
} else {
  alert('The File APIs are not fully supported in this browser.');

function handleFileSelect(evt) {
  var f =[0]; // FileList object
  var reader = new FileReader();
  // Closure to capture the file information.
  reader.onload = (function(theFile) {
    return function(e) {
      var binaryData =;
      //Converting Binary Data to base 64
      var base64String = window.btoa(binaryData);
      //showing file converted to base64
      document.getElementById('base64').value = base64String;
      alert('File converted to base64 successfuly!\nCheck in Textarea');
  // Read in the image file as a data URL.