Javascript实用函数

function addLoadEvent(fun) {
var oldonload = window.onload;
if(typeof(window.onload) != 'function') {
window.onload = fun;
} else {
window.onload = function() {
oldonload();
fun();
}
}
}
//function insertAfter(newElement, targentElement)
function insertAfter(insertedNode, adjacentNode) {
var parent = adjacentNode.parentNode;
if(parent.lastChild == adjacentNode) {
parent.appendChild(insertedNode);
} else {
parent.insertBefore(insertedNode, adjacentNode.nextSibling);
}
}