function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      oldonload();
      func();
    }
  }
}



function clearSearch() {
	var searchbox = document.getElementById('searchbox');
	searchbox.onfocus = function(){
		searchbox.setAttribute('value' , '');
	}
	searchbox.onblur = function(){
		searchbox.setAttribute('value' , 'part # or description');
	}
}

addLoadEvent(clearSearch);