is it possible to programatically set the DataFormatString for a field in a datagrid?

[Fred Exley]

I'm trying to change the following DataFormatString dynamically in my C#
code, depending on various criteria:

<asp:BoundField DataField="NUTR_VAL" DataFormatString="{0:00.0000}"
HeaderText="zzzzzz"

Works fine as a static definition, but can the same setting above be set
programatically? thanks -Fred