protected void Login_Click(object sender, EventArgs e) { loginB.userName = UserName.Text; loginB.password = PassLog.Text; UserName.Text = ""; PassLog.Text = ""; int res = lb.CheckLogin(loginB); if (res == 0) { string script = "<script type=\"text/javascript\">alert('Incorrect username or password!!!');</script>"; ClientScript.RegisterClientScriptBlock(this.GetType(), "Alert", script); Response.Redirect("Home.aspx"); } else { Session["userName"] = loginB.userName; Response.Redirect("Main.aspx"); } }