邮箱的验证

<script type="text/javascript">
    //验证邮箱格式
    function isEmail() {
        var email = document.getElementById("zh_e").value;
        if(email == "") {
            alert("请输入邮箱！");
            document.getElementById("zh_e").focus();
            return false;
        }
        var pattern = /^([a-zA-Z0-9]+[_|\_|.]?)*[a-zA-Z0-9]+@([a-zA-Z0-9]+[_|\_|.]?)*[a-zA-Z0-9]+.[a-zA-Z]{2,3}$/;
        strEmail = pattern.test(email);
        if(strEmail) {
            return true;
        } else {
            alert("邮箱格式不正确！");
        }
    }
</script>
实现功能：当鼠标焦点离开文本框时触发该事件。onblur=“isEmail” [ onblur()失去焦点时触发事件 ]

<body>
    <input type="text" maxlength="32" style="220px;" onblur="isEmail()" id="zh_e" />
</body>