We can add 2 fields and display in a combo box:
Ex: ID+" "+CustName
When you are doing this through query,it will be customary to mention ID+" "+CustName
If you want to display two column fields in the DropDownList with some separator, then this one comes in the picture. Example: letâ€™s say database columns are ID and CustName, but you want to display ID#CusttName in the DropDownList, then you will put â€œ#â€ in the DisplayColumnSeparator property.
Here is a link which tells abt combo box: