focus js

JavaScript
document.getElementById("ThingToSetFocusOn").focus();focusMethod = function getFocus() {          
  document.getElementById("myButton").focus();
}focusMethod = function getFocus() {           
  document.getElementById("myTextField").focus();
}// ElementObject grabs focus

 HTMLElementObject.focus()<input type="text" id="myTextField" value="Text field.">
<p></p>
<button type="button" onclick="focusMethod()">Click me to focus on the text field!</button>
// GIVE FOCUS TO A TEXT FIELD IMMEDIATELY AFTER WINDOW LOADS

 window.onload = function() {
  document.getElementById("myText").focus();
}; 
Source

Also in JavaScript: