JavaScript通过RegExp实现客户端验证

@Html.TextBox("txt",null, new {@style="width:300;",onkeypress="return RegValidateIsDigit(event)" })

<script type="text/javascript">
    function RegValidateIsDigit(e) {
        var KeyChar;
        debugger;
        ////判断浏览器
        if (window.event)  //IE
        {
            KeyChar = e.keyCode;
        }
        else if (e.which)///FireFox等
        {
            KeyChar = e.which;
        }
        var str = String.fromCharCode(KeyChar);   ///通过UniCode编码来来查找相应的字符
        return regIsDigit(str);
    }

    function regIsDigit(fData) {
        ///定义正则进行匹配
        var reg = new RegExp("^[0-9]$");
        return (reg.test(fData));
    }
</script>

var reg = new RegExp("^[0-9]$");

var reg = new RegExp("\\d$");

var reg=/\d$/;

    function RegValidateIsChinese(str) {
        //var reg = new RegExp("^[\u4e00-\u9fa5]+$");
        var reg = /^[\u4E00-\u9FA5]+$/;
        var str=document.getElementById("text").value;
        return (reg.test(str));
    }

    function RegValidateIsEmail(str) {
        //var reg = /^([a-zA-Z0-9_-])+@@([a-zA-Z0-9_-])+((\.[a-zA-Z0-9_-]{2,3}){1,2})$/;
        var reg=/^\w+((-\w+)|(\.\w+))*@@{1}\w+\.{1}\w{2,4}(\.{0,1}\w{2}){0,1}/ig;
        if (reg.test(str)) {
            alert("是邮箱");
        }
        else {
            alert("格式不对");
        }
    }