避免多次提交表单

//避免多次提交表单
EventUtil.addHandler(form,"submit",function(event){
//获取事件对象
  event=EventUtil.getEvent(event);
var target=EventUtil.getEvent(event);
//取得提交按钮
var btn=target.elements["submit-btn"];
//禁用它
btn.disabled=true;
});