Hi Paul,
Based on my understanding, you want to bind the ComboBox to a table (may be datatable) and show multi-column when dropped down. That ComboBox will be used in DataGridView. Do I understand it correctly?
If so, here is an example of multi-column ComboBox.
http://www.codeproject.com/KB/combobox/multicolumncombo.aspx?msg=1336374 When you use it in DataGridView, you can handle the CellBeginEdit event to place the ComboBox below the current editing cell. Please download the whole sample from my skydrive.
http://cid-380a93ce0876cf8b.skydrive.live.com/self.aspx/Microsoft%20MSDN%20Work/Solution%20Code/DGVMultiColumnComboBox%5E52009.10.2%5E6.zip If you have anything unclear, please feel free to tell me.
Sincerely,
Kira Qian
Send us any feedback you have about the help from MSFT at EMAIL REMOVED
Please remember to mark the replies as answers if they help and unmark them if they provide no help.
Welcome to the
All-In-One Code Framework!