SOURCE

var ipt=document.getElementById('ipt');
var but=document.getElementById('but');
var box=document.getElementById('box');
// event=new Event(
// 	'look',
//   {
//     'bubbles':true,
//     'cancelable':true
//   }
// );

function callBack(event) {
  var tag=event.currentTarget.tagName;
  console.log('tag ===>'+ tag);
}
box.addEventListener('click',callBack,true);
var click=new Event('click');
btn.dispatchEvent(click);


document.dispatchEvent(event);
//btn.parentDefault(false);

<div id="box">
<input type="text" id="ipt" />
  <input type="button" id="but"  value="确认"/>
  </div>