Help on C# tutorials, VB.Net, AJAX, Javascript, ASP.Net, SQL server, Win form

protected void RadComboBox1_SelectedIndexChanged(object sender, Telerik.Web.UI.RadComboBoxSelectedIndexChangedEventArgs e)         {             // Get the Country DropDownList first.             RadComboBox ddlBranch = (RadComboBox)sender;             // Get the current GridView Row, from which the DropDownList is selected.             GridEditableItem currentRow = (GridEditableItem)ddlBranch.NamingContainer;             // Now let's find the City DropDownList on the same GridView Row.             DropDownList ddlCity = (DropDownList)currentRow.FindControl("ddlAgent");             if (ddlBranch != null && ddlBranch.SelectedIndex > 0 && ddlCity != null)             {                 relife_part2Entities db = new relife_part2Entities();                 int? companyidfk=Convert.ToInt32(ddlBranch.SelectedValue);                 ddlCity.DataSource = db.tbl_policymaster.Where(x => x.companyidfk == companyidfk).ToList();                 dd