asp.net利用js进行form验证表单

.cs后台代码
// 在此处放置用户代码以初始化页面
Button1register.Attributes.Add("onclick","return checkform(form)");
aspx页面脚本
<script language="JavaScript">
function checkform(Register)
{
if (Register.LoginId.value=="")
{
alert("请输入会员登陆名!");
Register.LoginId.focus();
return false;
}
if (Register.password1.value=="")
{
alert("请输入密码!");
Register.password1.focus();
return false;
}
if (Register.password2.value=="")
{
alert("请输入确认密码!");
Register.password2.focus();
return false;
}
if (Register.password1.value != Register.password2.value)
{
alert("两次密码必须一致!");
Register.password1.focus();
return false;
}
if (Register.NickName.value=="")
{
alert("请输入您的真实姓名!");
Register.NickName.focus();
return false;
}
if(Register.Email.value.length!=0)
{
if (Register.Email.value.charAt(0)=="." ||
Register.Email.value.charAt(0)=="@"||
Register.Email.value.indexOf('@', 0) == -1 ||
Register.Email.value.indexOf('.', 0) == -1 ||
Register.Email.value.lastIndexOf("@")==Register.Email.value.length-1 ||
Register.Email.value.lastIndexOf(".")==Register.Email.value.length-1)
{
alert("Email的格式不正確！");
Register.Email.focus();
return false;
}
}
else
{
alert("Email的不能为空！");
Register.Email.focus();
return false;
}

Register.submit();
}
</script>
function checkform(Register)
{
if (Register.LoginId.value=="")
{
alert("请输入会员登陆名!");
Register.LoginId.focus();
return false;
}
if (Register.password1.value=="")
{
alert("请输入密码!");
Register.password1.focus();
return false;
}
if (Register.password2.value=="")
{
alert("请输入确认密码!");
Register.password2.focus();
return false;
}
if (Register.password1.value != Register.password2.value)
{
alert("两次密码必须一致!");
Register.password1.focus();
return false;
}
if (Register.NickName.value=="")
{
alert("请输入您的真实姓名!");
Register.NickName.focus();
return false;
}

if(Register.Email.value.length!=0)
{
if (Register.Email.value.charAt(0)=="." ||
Register.Email.value.charAt(0)=="@"||
Register.Email.value.indexOf('@', 0) == -1 ||
Register.Email.value.indexOf('.', 0) == -1 ||
Register.Email.value.lastIndexOf("@")==Register.Email.value.length-1 ||
Register.Email.value.lastIndexOf(".")==Register.Email.value.length-1)
{
alert("Email的格式不正確！");
Register.Email.focus();
return false;
}
}
else
{
alert("Email的不能为空！");
Register.Email.focus();
return false;
}

Register.submit();
}

function checkform(Register)
{
if (Register.LoginId.value=="")
{
alert("请输入会员登陆名!");
Register.LoginId.focus();
return false;
}
if (Register.password1.value=="")
{
alert("请输入密码!");
Register.password1.focus();
return false;
}
if (Register.password2.value=="")
{
alert("请输入确认密码!");
Register.password2.focus();
return false;
}
if (Register.password1.value != Register.password2.value)
{
alert("两次密码必须一致!");
Register.password1.focus();
return false;
}
if (Register.NickName.value=="")
{
alert("请输入您的真实姓名!");
Register.NickName.focus();
return false;
}

if(Register.Email.value.length!=0)
{
if (Register.Email.value.charAt(0)=="." ||
Register.Email.value.charAt(0)=="@"||
Register.Email.value.indexOf('@', 0) == -1 ||
Register.Email.value.indexOf('.', 0) == -1 ||
Register.Email.value.lastIndexOf("@")==Register.Email.value.length-1 ||
Register.Email.value.lastIndexOf(".")==Register.Email.value.length-1)
{
alert("Email的格式不正確！");
Register.Email.focus();
return false;
}
}
else
{
alert("Email的不能为空！");
Register.Email.focus();
return false;
}

Register.submit();
}

function checkform(Register)
{
if (Register.LoginId.value=="")
{
alert("请输入会员登陆名!");
Register.LoginId.focus();
return false;
}
if (Register.password1.value=="")
{
alert("请输入密码!");
Register.password1.focus();
return false;
}
if (Register.password2.value=="")
{
alert("请输入确认密码!");
Register.password2.focus();
return false;
}
if (Register.password1.value != Register.password2.value)
{
alert("两次密码必须一致!");
Register.password1.focus();
return false;
}
if (Register.NickName.value=="")
{
alert("请输入您的真实姓名!");
Register.NickName.focus();
return false;
}

if(Register.Email.value.length!=0)
{
if (Register.Email.value.charAt(0)=="." ||
Register.Email.value.charAt(0)=="@"||
Register.Email.value.indexOf('@', 0) == -1 ||
Register.Email.value.indexOf('.', 0) == -1 ||
Register.Email.value.lastIndexOf("@")==Register.Email.value.length-1 ||
Register.Email.value.lastIndexOf(".")==Register.Email.value.length-1)
{
alert("Email的格式不正確！");
Register.Email.focus();
return false;
}
}
else
{
alert("Email的不能为空！");
Register.Email.focus();
return false;
}

Register.submit();
}