مساعدة عاجلة في شرح هذه الاكواد #c

using System;

using System.Collections;

using System.Configuration;

using System.Data;

using System.Linq;

using System.Web;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.HtmlControls;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Xml.Linq;

using System.Data.SqlClient;

public partial class Login : System.Web.UI.Page

{

string StrConn = ConfigurationManager.AppSettings["ConnString"];

protected void Page_Load(object sender, EventArgs e)

{

}

protected void btnSignin_Click(object sender, EventArgs e)

{

Session["AdminU"] = txtUsername.Text;

Session["AdminP"] = txtPass.Text;

SqlDataAdapter daUser = null;

DataSet dsUser = null;

try

{

daUser = new SqlDataAdapter("SELECT User_name,Pass from Registration where User_name='" + txtUsername.Text + "' and pass='" + txtPass.Text + "' ", StrConn);

dsUser = new DataSet();

daUser.Fill(dsUser);

if (dsUser.Tables[0].Rows.Count == 0)

{

lblUserName.Visible = true;

lblUserName.Text = "The " + txtUsername.Text + " does not exist or the password is incorrect";

}

else

{

Response.Redirect("Main.aspx");

}

}

catch// (Exception ex)

{

throw;

}

finally

{

}

}

}

{

{