如何在脚本中将文件正确上传为 base64

Question

我试图在javascript中上传文件作为base64，但它抛出了错误。

TypeError: FileReader.readAsDataURL: Argument 1 does not implement interface Blob.

这是代码

  <input id="file" type="file"/>

  <button id="button">upload</button>

document.getElementById('button').addEventListener('click', function() {

  var files = document.getElementById('file').files;

  var reader = new FileReader();

   reader.readAsDataURL(files);

   reader.onload = function () {

     console.log(reader.result);

    alert('my file: ' +reader.result);

   };

   reader.onerror = function (error) {

     console.log('Error: ', error);

   }

});

Answer 1

const toBase64 = file => new Promise((resolve, reject) => {&nbsp; &nbsp; const reader = new FileReader();&nbsp; &nbsp; reader.readAsDataURL(file);&nbsp; &nbsp; reader.onload = () => resolve(reader.result);&nbsp; &nbsp; reader.onerror = error => reject(error);});async function Main() {&nbsp; &nbsp;const file = document.querySelector('#myfile').files[0];&nbsp; &nbsp;console.log(await toBase64(file));}Main();