ComboBox problem

[C# Programming]

Dear coders,

I think i am fallen in simple problem but i can't fix it.Please Help me.
Problem is:i take a combobox in a datagridview. i just change the Column type and i wrote this code:

RoomTypeBLL objRoomTypeBLL = new RoomTypeBLL();
colType.DataSource = objRoomTypeBLL.GetAllRoomTypeData();

colType.ValueMember = "fldRoomTypeAutoID";
colType.DisplayMember = "fldTypeName";

How i save combobox value member value into database?

Thanks in advance