[Vuejs]-I tried to add multiple images using vue js html, but getting error as illegal invocation?

The problem is with how you upload files using ajax.

The generally recommended way to do it is to use FormData.

I am able to get it to work without having Illegal invocation error in https://jsfiddle.net/jacobgoh101/p6yuzm26/12/ .

handleSubmit: function(e) {
  var vm = this;
  var form = $('#addForm form')[0];
  var data = new FormData(form);

  $.ajax({
    url: 'http://localhost:4000/s/',
    data: data,
    type: 'POST',
    //dataType: 'json',
    enctype: 'multipart/form-data',
    processData: false,
    contentType: false,
    cache: false,
    success: function(e) {
       // ...
    }
  });
  return false;
},

This is the reference that I followed => https://coderwall.com/p/p-n7eq/file-uploads-with-jquery-html5-and-formdata .

Hope this helps.