<asp:ImageButton ID="imgRegister" runat="server" ImageUrl="Images/qdzc.gif" OnClientClick="return checkForm()" OnClick="imgRegister_Click"  />

function checkForm() {
            if (checkUserName() && checkPass() && checkEmail() && chkMobile() && chkUName()) {
                return true;
            } else {
                return false;
            }
        }
        //用户名非空+长度+合法性验证
        function checkUserName() {
            var name = document.getElementById("userid");
            if (name.value == "") {
                alert("请输入登录名");
                name.focus();
                return false;
            }
            if (name.value.length < 4 || name.value.length > 16) {
                alert("登录名输入的长度4-16个字符");
               
                name.select();
                return false;
            }
            for (var i = 0; i < name.value.length; i++) {
              
                var charTest = name.value.toLowerCase().charAt(i);
                if ((!(charTest >= '0' && charTest <= '9')) && (!(charTest >= 'a' && charTest <= 'z')) && (charTest != '_')) {
                    alert("用户名包含非法字符，只能包括字母,数字和下划线");
                    name.select();
                    return false;
                }
            }
            return true;
        }
        //密码非空+长度+密码确认验证
        function checkPass() {
           
            var pass = document.getElementById("txtPass");
            var rpass = document.getElementById("txtRPass");
            if (pass.value == "") {
                alert("密码不能为空");
                pass.focus();
                return false;
            } if (pass.value.length < 6 || pass.value.length > 16) {
                alert("密码长度为6-16个字符");
                pass.select();
                return false;
            }
            if (rpass.value != pass.value) {
                alert("确认密码与密码输入不一致");
                rpass.select();
                return false;
            }
            return true;
        }

        //电子邮件验证
        function checkEmail() {

            var strEmail = document.getElementById("txtEmail");
            if (strEmail.value.length == 0) {
                alert("电子邮件不能为空!");
                strEmail.focus();
                return false;
            }
            if (strEmail.value.indexOf("@", 0) == -1) {
                alert("电子邮件格式不正确\n必须包含@符号！");
                strEmail.select();
                return false;
            }
            if (strEmail.value.indexOf(".", 0) == -1) {
                alert("电子邮件格式不正确\n必须包含.符号！");
                strEmail.select();
                return false;
            }
            return true;
        }

        //手机中号码验证
        String.prototype.Trim = function() {
            var m = this.match(/^\s*(\S+(\s+\S+)*)\s*$/);
            return (m == null) ? "" : m[1];
        }

        String.prototype.isMobile = function() {
            return (/^(?:13\d|15[89])-?\d{5}(\d{3}|\*{3})$/.test(this.Trim()));
        }

        String.prototype.isTel = function() {
            //"兼容格式: 国家代码(2到3位)-区号(2到3位)-电话号码(7到8位)-分机号(3位)"   
            //return (/^(([0\+]\d{2,3}-)?(0\d{2,3})-)?(\d{7,8})(-(\d{3,}))?$/.te