JAVASCRIPT

set focus javascript

document.getElementById("ThingToSetFocusOn").focus();

set focus on input field javascript

window.onload=function(){
 document.getElementById("id_here").focus();
}
// id_here = put the id of the HTML element where you want to set focus.

focus element javascript

focusMethod = function getFocus() {
  document.getElementById("myTextField").focus();
}

js focus a div

<!-- In order to do it, you need to assign a tabindex... -->
<div tabindex="0">Hello World</div>