How to Bind Country, State, City using Ajax Update Panel

I am working on some project there i have 2 drop down lists and one Textbox in Update panel1. here i am binding the Names of PG from database to dropdownlist1(DDPGNames) and binding the PG rooms to dropdownlist2(DDRoomNumber) based first dropdownlist (it's like Country and state thing) now if i select any Room number in 2nd Dropdownlist the room rent has to dispaly automatically in textbox. for this i am writing this code on DDRoomNumber SelectIndexChanged Event. but my problem is DDRoomNumber is not taking selected room Number (It is taking Only First Value) if i select any other room in dropdown list it's going first one only. see here my code: protected void DDRoomNumber_SelectedIndexChanged(object sender, EventArgs e) { txtRent.Enabled = true; MySqlConnection Con = new MySqlConnection(MyConString); MySqlCommand Cmd = Con.CreateCommand(); string S = "SELECT*FROM pg_room_list WHERE Room_Num ='" DDRoomNumber.SelectedItem.Text "' AND Room_PG_ID ='" DDPGNames.SelectedValue "';"; Cmd = new MySqlCommand(S, Con); MySqlDataReader Dr; Con.Open(); Dr = Cmd.ExecuteReader(); while (Dr.Read()) { string SRoom_Rent = Dr.GetString("Room_Rent"); txtRent.Text = SRoom_Rent; } Con.Close(); } Pls give me some solution. Thanks

Thanks Tanuj

thanks....this post is good...

please can you help me regarding the sql database and tables you have created for this article? Thanks in advance

Hi Guys This is working Fine but i think in this senario there is no need to add Triggers with update panel as below: <Triggers > <asp:AsyncPostBackTrigger ControlID ="ddlcity" /> </Triggers> It doesnt craete any problem but it is not needed here. Try to use without trigger and please reply .