jquery upload preview image code example

Example 1: preview image before upload

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<form runat="server">
  <input type='file' id="imgInp" />
  <img id="blah" src="#" alt="your image" />
</form>

<script>
function readURL(input) {
  if (input.files && input.files[0]) {
    var reader = new FileReader();
    
    reader.onload = function(e) {
      $('#blah').attr('src', e.target.result);
    }
    
    reader.readAsDataURL(input.files[0]); // convert to base64 string
  }
}

$("#imgInp").change(function() {
  readURL(this);
});
</script>

Example 2: how to display image before upload in jhtml

function display(input) {
   if (input.files && input.files[0]) {
      var reader = new FileReader();
      reader.onload = function(event) {
         $('#myid').attr('src', event.target.result);
      }
      reader.readAsDataURL(input.files[0]);
   }
}

$("#demo").change(function() {
   display(this);
});