WebForm Customer Validator的客户端验证怎么做急
现在本人初学asp.net 网站制作,现在要做一个注册页面,我想在用户填入username的时候检查数据库中的username是否存在,如果存在则在Customer validator中显示Error:user exists Please change。这个验证我想在客户端上用js实现,现在写了如下代码:
js-------:
function ValidationFunction(source, arguments) {
var username = document.getElementById("txtUsername").value;
alert(username);
var obj = new ActiveXObject("Microsoft.XMLHTTP");
obj.open("get", "RepeatNameValidator.aspx?username=" + username + "", false);
obj.send();
var stresult = obj.response.text;
if (Number(stresult) == 1) {
arguments.isValid = false;
}
else {
arguments.isValid = true;
}
}
数据库判断 页面代码----------
string Conn = WebConfigurationManager.ConnectionStrings["cn"].ConnectionString;
SqlConnection cn = new SqlConnection(Conn);
SqlDataReader sdr;
SqlDataAdapter sda;
SqlCommand cmd;
cmd = new SqlCommand();
cmd.CommandText = "select username from userInfo ";
cmd.Connection = cn;
if ( Vusername!= null)
{
cn.Open();
sdr = cmd.ExecuteReader();
while (sdr.Read())
{
if (sdr[0].ToString().Equals(Vusername))
{
Response.Write("0");
break;
}
else
{
Response.Write("1");
}
}
sdr.Close();
cn.Close();
}
customer Validator 页面代码:-----
<asp:TextBox ID="txtUsername" runat="server"></asp:TextBox>
<asp:CustomValidator ID="CVUserName" runat="server" ErrorMessage="Invalid" ForeColor="Red"
ControlToValidate="txtUsername" ClientValidationFunction="ValidationFunction" ></asp:CustomValidator>
单独测试aspx的页面时候,页面当中能够显示0或1,但是在 使用ClientValidationFunction时,js无法调用,也不报错,
求大神指导