Question

Imagine that I introduced an extension method on string type called Shorten() which gets only the first 50 characters and returns it.

If I want to call this method on a GridView’s bound field, what is the simplest way of calling it so that on screen I see the shorten version of the message.

<!-- TODO: How to call .Shorten() extension method on the ItemDescription in markup: --!>
<asp:BoundField HeaderText="Items" DataField="ItemDescription"...> 

Answer 1

Make that column a template column:

<itemtemplate>
<asp:label id="lblItemDesc" runat="server" Text='<%=string.Format(Eval("ItemDescription").ToShorten()))%>' />
</itemtemplate>

And make sure ToShorten takes an object, not a string since Eval returns object.

*Above code not tested but pretty sure is very close.

Another alternative:

Modify your class and add a ItemDescriptionShorten property that would be like this:

public string ItemStringDescriptionShorten { get {return ItemDescription.ToShortern();}}

Now bind to that property instead of ItemDescription