Column HeaderText set at runtime?

[Mark A Gregory]

I have tried to put a string in the codebehind and to load this at runtime,
but it does not seem to work.
I would appreciate ideas on how to load the Column HeaderText from a
dataset. This dataset is
different than the one that datagrid is bound to.

<asp:BoundColumn DataField="strPosition1" SortExpression="strPosition1"
ReadOnly="True" HeaderText="<%= strHeaderText1 %>"></asp:BoundColumn>

in the code behind I have

protected string strHeaderText1 = "Test";

thank you
mark