How to display selected image without sending data to server?

You can use FileReader web-api object for this, see this snippet:

the HTML

<input id="src" type="file"/> <!-- input you want to read from (src) -->
<img id="target"/> <!-- image you want to display it (target) -->

the javascript

function showImage(src,target) {
  var fr=new FileReader();
  // when image is loaded, set the src of the image where you want to display it
  fr.onload = function(e) { target.src = this.result; };
  src.addEventListener("change",function() {
    // fill fr with image data    
    fr.readAsDataURL(src.files[0]);
  });
}

var src = document.getElementById("src");
var target = document.getElementById("target");
showImage(src,target);