<form id="form1" runat="server">


   
<input id="txtUserName" type="text" runat="server">
<ASP:RequiredFieldValidator ControlToValidate="txtUserName"
       Display="Static" ErrorMessage="*" runat="server"
       ID="vUserName" />







        <input id="txtUserPass" type="password" runat="server">
<ASP:RequiredFieldValidator ControlToValidate="txtUserPass"
      Display="Static" ErrorMessage="*" runat="server"
      ID="vUserPass" />



<p>

</p>
<input type="submit" Value="Logon" runat="server" ID="cmdLogin"><p>

</p>
<ASP:CheckBox id="chkPersistCookie" runat="server" autopostback="false" />
</form>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data.SqlClient;
using System.Web.Security;

namespace MRAApplication
{
    public partial class _1__0__0__0_LoginScreen : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            this.cmdLogin.ServerClick += new System.EventHandler(this.cmdLogin_ServerClick);
        }

        private bool ValidateUser(string userName, string passWord)
        {
            SqlConnection conn;
            SqlCommand cmd;
            string lookupPassword = null;

            // Check for invalid userName.
            // userName must not be null and must be between 1 and 15 characters.
            if ((null == userName) || (0 == userName.Length) || (userName.Length > 15))
            {
                System.Diagnostics.Trace.WriteLine("[ValidateUser] Input validation of userName failed.");
                return false;
            }

            // Check for invalid passWord.
            // passWord must not be null and must be between 1 and 25 characters.
            if ((null == passWord) || (0 == passWord.Length) || (passWord.Length > 25))
            {
                System.Diagnostics.Trace.WriteLine("[ValidateUser] Input validation of passWord failed.");
                return false;
            }

            try
            {
                // Consult with your SQL Server administrator for an appropriate connection
                // string to use to connect to your local SQL Server.
                conn = new SqlConnection("databaseConnect");
                conn.Open();

                // Create SqlCommand to select pwd field from users table given supplied userName.
                cmd = new SqlCommand("Select Password from Users where User=@userName", conn);
                cmd.Parameters.Add("@userName", System.Data.SqlDbType.VarChar, 25);
                cmd.Parameters["@userName"].Value = userName;

                // Execute command and fetch pwd field into lookupPassword string.
                lookupPassword = (string)cmd.ExecuteScalar();

                // Cleanup command and connection objects.
                cmd.Dispose();
                conn.Dispose();
            }
            catch (Exception ex)
            {
                // Add error handling here for debugging.
                // This error message should not be sent back to the caller.
                System.Diagnostics.Trace.WriteLine("[ValidateUser] Exception" + ex.Message);
            }

            // If no password found, return false.
            if (null == lookupPassword)
            {
                // You could write failed login attempts here to event log for additional security.
                return false;
            }

            // Compare lookupPassword and input passWord, using a case-sensitive comparison.
            return (0 == string.Compare(lookupPassword, passWord, false));

        }

        private void cmdLogin_ServerClick(object sender, System.EventArgs e)
        {
            if (ValidateUser(txtUserName.Value, txtUserPass.Value))
            {
                FormsAuthenticationTicket tkt;
                string cookiestr;
                HttpCookie ck;
                tkt = new FormsAuthenticationTicket(1, txtUserName.Value, DateTime.Now,
          DateTime.Now.AddMinutes(30), chkPersistCookie.Checked,"your custom data");
                cookiestr = FormsAuthentication.Encrypt(tkt);
                ck = new HttpCookie(FormsAuthentication.FormsCookieName, cookiestr);
                if (chkPersistCookie.Checked)
                    ck.Expires = tkt.Expiration;
                ck.Path = FormsAuthentication.FormsCookiePath;
                Response.Cookies.Add(ck);

                string strRedirect;
                strRedirect = Request["ReturnUrl"];
                if (strRedirect == null)
                    strRedirect ="default.aspx";
                Response.Redirect(strRedirect, true);
            }
            else
                Response.Redirect("1.0.0.0_LoginScreen.aspx", true);
        }
     }
    }

protected void cmdLogin_ServerClick(object sender, System.EventArgs e)
{
    if (String.Equals(txtUserName.Value,"johndoe",
        StringComparison.InvariantCultureIgnoreCase) &&
        String.Equals(txtUserPass.Value,"123456",
        StringComparison.InvariantCultureIgnoreCase))
    {
        var roles = new[] {"Administrators"};

        var ticket = new FormsAuthenticationTicket(1,
            txtUserName.Value,
            DateTime.Now,
            DateTime.Now.AddMinutes(30),
            chkPersistCookie.Checked,
            string.Join(",", roles),
            FormsAuthentication.FormsCookiePath);

        var cookie = new HttpCookie(FormsAuthentication.FormsCookieName,
            FormsAuthentication.Encrypt(ticket));

        if (chkPersistCookie.Checked)
            cookie.Expires = ticket.Expiration;

        Response.Cookies.Add(cookie);

        string returnUrl = Request["ReturnUrl"];
        if (returnUrl == null)
            returnUrl ="default.aspx";
        Response.Redirect(returnUrl, true);
    }
    else
        Response.Redirect("1.0.0.0_LoginScreen.aspx", true);
}

// Global.asax.cs
public class Global : HttpApplication
{
    void Application_AuthenticateRequest(object sender, EventArgs e)
    {
        HttpCookie decryptedCookie =
            Context.Request.Cookies[FormsAuthentication.FormsCookieName];

        if (decryptedCookie != null)
        {
            FormsAuthenticationTicket ticket =
                FormsAuthentication.Decrypt(decryptedCookie.Value);

            string[] roles = ticket.UserData.Split(new[] {","},
                 StringSplitOptions.RemoveEmptyEntries);

            var identity = new GenericIdentity(ticket.Name);
            var principal = new GenericPrincipal(identity, roles);

            HttpContext.Current.User = principal;
            Thread.CurrentPrincipal = HttpContext.Current.User;
        }
    }
}

public partial class _Default : Page
{
    protected void Page_Load(object sender, EventArgs e)
    {    
        if (User.Identity.IsAuthenticated)
        {
            string username = User.Identity.Name;

            bool isAdministrator = User.IsInRole("Administrators");
        }
    }
}