Hi Nat,

To start, you are correct in setting the DataSource after the DispalyMember
and ValueMember.  This is more efficient because the control only get bound
once instead of 3 times.  You are also correct in that if the datasource
becomes null the DisplayMember will be reset to string.Empty.

The two things I can think of is.  The first is redesign so that you the
datasource does not become null.  Use a datasource that can be empty without
being null like an ArrayList or DataTable.  The second is that, as you said,
set the DisplayMember each time you set the bound datasource object to
something.  In this case I would use a method that sets the bound datasource
object where you include setting the DisplayMember value so that it is in
one spot.

Note: I don't believe by setting the DisplayMember after the DataSource will
work for you. You would still run into the same problem of the DispalyMember
being reset.

Take care,

Tom Krueger

My Blog - http://weblogs.asp.net/tom_krueger
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