Since the expression is in a string literal, you have to use SQL syntax, thus "
<>
" is the correct inequality operator.
Saying "but it not work" does not give us enough information to help you further. Put your code into a
try/catch
block so you can see the exception being generated (if any).
Go here for a complete list of valid operators for the Select method expression. You'll need to scroll about halfway down the page:
DataColumn.Expression Property (System.Data)[
^]