只有三次抽奖机会！

<input type="button" id="btnDOM2Test" value="测试DOM2事件处理"/>
<input type="button" id="btnDelDOM2Test" value="测试DOM2删除事件处理"/>
<script type="text/javascript">
var sayHi = function () {
alert('Hello!');
}

var btnDOM2Test = document.getElementById('btnDOM2Test');
btnDOM2Test.addEventListener('click',function () {
alert('您单击的是：' + this.value);
},false);

btnDOM2Test.addEventListener('click',sayHi,false);

var btnDelDOM2Test = document.getElementById('btnDelDOM2Test');

var del = function () {
btnDOM2Test.removeEventListener('click',function () {
alert('您单击的是：' + this.value);
},false);
btnDOM2Test.removeEventListener('click',false);
}
btnDelDOM2Test.addEventListener('click',del,false);

//IE9+
//btnDOM2Test.attachEvent("onclick",sayHi);
//btnDOM2Test.attachEvent("onclick",function () {
// alert("IE事件绑定!");
//});

<label for="txtPhoneNum">请输入手机号码
<input type="text" id="txtPhoneNum"/>
<script type="text/javascript">
var txtPhoneNum = document.getElementById('txtPhoneNum');
EventUtil.addHandler(txtPhoneNum,'keypress',function () {
var e = EventUtil.getEvent();
//alert(e.keyCode);
//都不是数字
if (e.keyCode < 48 || e.keyCode > 57) {
EventUtil.preventDefault(e);
}
});

<form id="frmDemo" action="submitPage.htm">

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