How can I use authentication & authorization tags only for my Admin, in web.config without using Login controls in asp.net
<p>I'm new in asp.net and I have a problem.
in my asp.net webdirectory I have some pages for users and an Admin Folder for administrator , I want to use some tags like authentication &amp; authorization in my web.config File to determine my administrator username and password and determine only the admin can use pages in the admin folder but my problem is I did'nt use any login control in my web for my users to sign in.I use some textboxes which give the users information and then I connect to my table in database and check their information and I want to know how can I do that with this condition?
I'll become so thankfull if any body help me.
users Sign in with thier emails and passwords
this is my code:</p>

<pre><code>       &lt;tr&gt;
        &lt;td&gt;
            &amp;nbsp;Email :
        &lt;/td&gt;
        &lt;td class="style1"&gt;
            &amp;nbsp;&lt;asp:TextBox ID="TextBox1" runat="server"&gt;&lt;/asp:TextBox&gt;
            &lt;br /&gt;

        &lt;/td&gt;

    &lt;/tr&gt;
     &lt;tr&gt;
        &lt;td&gt;
            &amp;nbsp;
        &lt;/td&gt;
        &lt;td class="style1"&gt;
            &amp;nbsp; &lt;asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" 
                ErrorMessage="please enter your email!" 
                ControlToValidate="TextBox1" 
                Display="Dynamic" ForeColor="#CC0000" ValidationGroup="SignIn"&gt;&lt;/asp:RequiredFieldValidator&gt;
            &lt;br /&gt;
            &lt;asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server" ErrorMessage="incorrect format!" ValidationExpression="\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*"  Display="Dynamic"  ForeColor="#CC0000" ControlToValidate="TextBox1" ValidationGroup="SignIn"&gt;&lt;/asp:RegularExpressionValidator&gt;
           &lt;br /&gt;

        &lt;/td&gt;

    &lt;/tr&gt;
    &lt;tr&gt;
        &lt;td&gt;
            &amp;nbsp;password:
        &lt;/td&gt;
        &lt;td class="style1"&gt;
            &amp;nbsp;&lt;asp:TextBox ID="TextBox2" runat="server" TextMode="Password" &gt;&lt;/asp:TextBox&gt;
           &lt;br /&gt;
        &lt;/td&gt;

    &lt;/tr&gt;
     &lt;tr&gt;
        &lt;td&gt;
            &amp;nbsp;
        &lt;/td&gt;
        &lt;td class="style1"&gt;
         &amp;nbsp;
            &lt;asp:RequiredFieldValidator ID="RequiredFieldValidator4" runat="server" ErrorMessage="Enter your password" ControlToValidate="TextBox2"  Display="Dynamic" ForeColor="#CC0000" ValidationGroup="SignIn" &gt;&lt;/asp:RequiredFieldValidator&gt;

        &lt;/td&gt;

    &lt;/tr&gt;
    &lt;tr&gt;
        &lt;td&gt;
            &amp;nbsp;
        &lt;/td&gt;
        &lt;td class="style1"&gt;
            &amp;nbsp;&lt;asp:Button ID="Button2" runat="server" Text="enter" 
                Width="123px" onclick="Button2_Click" ValidationGroup="SignIn" /&gt;
        &lt;/td&gt;
</code></pre>

<blockquote>
  <p>I have changed it:</p>
</blockquote>

<pre><code>    protected void Button2_click(object sender, EventArgs e)
   {
     if (Membership.ValidateUser(TextBox1.Text.Trim(), TextBox2.Text.Trim()))
    {
        if (Roles.IsUserInRole(TextBox1.Text.Trim(), "Admin"))
        {
            Response.Redirect("Admin/Default.aspx");
            Session["user"] = "admin";
        }
       // ad.Text = "admin";
    }
    else
    {
      int c = -1;
    SqlConnection cn2 = new SqlConnection();
    cn2.ConnectionString = "server = . ; database = mobile_store ; Trusted_Connection=true";
    DataTable tb = new  DataTable();

    SqlCommand cmd2 = new SqlCommand();
    cmd2.Connection = cn2;
    cmd2.CommandType = CommandType.StoredProcedure;
    cmd2.CommandText = "Check_Email_Pass";
    cmd2.Parameters.AddWithValue("@mail", TextBox1.Text.Trim());
    cmd2.Parameters.AddWithValue("@pass", TextBox2.Text.Trim());
    cmd2.Parameters.Add("@res", SqlDbType.Int);    
    cmd2.Parameters["@res"].Direction = ParameterDirection.Output;

    SqlDataAdapter da = new SqlDataAdapter(cmd2);
    da.Fill(tb);
    try
    {
        cn2.Open();
        cmd2.ExecuteNonQuery();
        c = Convert.ToInt32(cmd2.Parameters["@res"].Value);

        switch (c)
        {
            case 1:
                {

                    Session["user"] = tb.Rows[0][0].ToString() + " " + tb.Rows[0][1].ToString();
                    Session["authenticate"] = true;
                    Session["id"] = Convert.ToInt32( tb.Rows[0][2]);

                    ((MasterPage)this.Master).lable2Visible = Session["user"].ToString();
                    Label2.Text = "Welcome" + " " + tb.Rows[0][0].ToString() + " " + tb.Rows[0][1].ToString();
                    TextBox1.Text = null;
                    if (Session["pagesource"] != null)
                    {
                        Response.Redirect((string)Session["pagesource"]);
                    }
                    else
                    {
                        Response.Redirect("~/user_page.aspx");
                    }

                }
                break;
            case 0:
                {
                    Label2.Text = "your password is wrong";

                }
                break;
            case 2:
                {

                    Label2.Text = "this email has registered before &lt;br/&gt; please sign up first";
                    TextBox3.Text = TextBox1.Text.Trim();
                }
                break;
            default:
                break;
        }

      }
    }

    catch (Exception ex)
    {
        Label1.Text = ex.ToString();

    }
    finally { cn2.Close(); }
   }
</code></pre>

<blockquote>
  <p>in my web.config file</p>
</blockquote>

<pre><code>     &lt;system.Web&gt;
    &lt;authentication mode="Forms"&gt;
        &lt;forms  timeout="20" slidingExpiration="true" cookieless="AutoDetect" protection="All" requireSSL="false" enableCrossAppRedirects="false" loginUrl="entrance_before_paying.aspx" &gt;
            &lt;credentials passwordFormat="Clear"&gt;
                &lt;user name="elmiragolshanff@yahoo.com" password="elmira" /&gt;
            &lt;/credentials&gt;
        &lt;/forms&gt;
    &lt;/authentication&gt;
    &lt;/system.web&gt;     


        &lt;location path="Admin"&gt;
    &lt;system.web&gt;
        &lt;authorization&gt;
            &lt;allow users="elmiragolshanff@yahoo.com" roles="Admin" /&gt;              
        &lt;/authorization&gt;

&lt;/location&gt;

    &lt;/system.web&gt;
</code></pre>
