preview image file upload javascript

1<input type="file" accept="image/*" onchange="loadFile(event)">
2<img id="output"/>
3<script>
4  var loadFile = function(event) {
5    var output = document.getElementById('output');
6    output.src = URL.createObjectURL(event.target.files[0]);
7    output.onload = function() {
8      URL.revokeObjectURL(output.src) // free memory
9    }
10  };
11</script>

1function display(input) {
2   if (input.files && input.files[0]) {
3      var reader = new FileReader();
4      reader.onload = function(event) {
5         $('#myid').attr('src', event.target.result);
6      }
7      reader.readAsDataURL(input.files[0]);
8   }
9}
10
11$("#demo").change(function() {
12   display(this);
13});