ASP.net: Dynamic BoundFields

Question

In a GridView, I'm trying to show either one column or an other using a public Boolean property:

   <Columns>
   ...

    <asp:BoundField Visible="<%= !ShowPurchaseDate %>" DataField="Published" HeaderText="Publicerad" SortExpression="PriceRange" DataFormatString="{0:yyyy.MM.dd}" HtmlEncode="false" />

    <asp:BoundField Visible="<%= ShowPurchaseDate %>" DataField="OrderDate" HeaderText="Köpt" SortExpression="OrderDate" DataFormatString="{0:yyyy.MM.dd}" HtmlEncode="false" />

   ...
  </Columns>

But I'm getting an error message saying that it's not possible to create a System.Boolean from a string that contains <% !ShowPurchaseDate %> for property Visisble.

How can I achive this?

UPDATE:

<%# !ShowPurchaseDate %> doesn't work either as there's no databinding going on.

Using a protected funktion doesn't work either (same error message as with property).

Answer 1

Provide a protected method in the code behind that returns the boolean property as a string.

Answer 2

You're code should be <%# !ShowPurchaseDate %>

Answer 3

I solved it through:

gridMain.Columns[ShowPurchaseDate ? 3 : 4].Visible = false;

Is this the best solution?

Answer 4

you could try calling a method instead of binding like shouldshowcolumn().