how to get response from web service to login page in c#

[WebService(Namespace = "http://tempuri.org/")]
   [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
   [System.ComponentModel.ToolboxItem(false)]
   // To allow this Web Service to be called from script, using ASP.NET AJAX, uncomment the following line.
    [System.Web.Script.Services.ScriptService]
   public class AdminService: System.Web.Services.WebService
   {
        [WebMethod]
        public string DoLogin(string UserName,string Password)
        {
           //Your Login checking Logic
DataTable resFromDB = DBContext.GetDataTable("select * from tblUSer where UserName = "+UserName+" && Password = "+Password+");
 string resString = "";
            if (resFromDB.Rows.count >0 )
            {
               
                if(resFromDB.Rows[0]["UserType"]=="Admin")
                   resString = "Admin_1_"+resFromDB.Rows[0]["UserID"].toString();
                else
                   resString = "User_1_"+resFromDB.Rows[0]["UserID"].toString();

            }
            else
            {
                 resString = "Error_2_0";
            }
            return resString;
        }
   }

protected void btnProcess_Click(object sender, EventArgs e)
        {
            
            AdminService ServiceObj = new AdminService();
string res = ServiceObj.DoLogin(txtUserName.Text, txtPassword.Text);
string successPart = res.split("_")[1];
            if (successPart  == 1)
            {
                //Login Success Logic
                if(res.split("_")[0]=="Admin")
                   Response.Redirect("AdminHome.aspx");
                else
                   Response.Redirect("EmployeeHome.aspx");
            }
            else
            {
                //Login Fail Logic
                Response.Redirect("Error.aspx");
            }
        }