I have the following snippet of code is which I am trying to format a 10 digit phone number field for display in a datagrid, and it is not working. Any suggestions would be appreciated. (pardon the formatting). The format mask (itemTemplate) is not reflected in display for the datagrid info.

<asp:TemplateColumn SortExpression="u_phone" HeaderText="Phone">
 <ItemTemplate>
   <asp:Label id=Label8 runat="server" Width=80
      Text='<%# Convert.ToString(DataBinder.Eval(Container, "DataItem.u_phone", "{0:(###)###-####}")) %>' / >
    </ItemTemplate>
 <EditItemTemplate>
   <asp:TextBox id=etxtPhone runat="server" MaxLength=10 Width=80
      Text='<%# DataBinder.Eval(Container, "DataItem.u_phone", "{0:##########}") %>' />
</asp:TemplateColumn>

It should work.what's the datatype of phone field?
Try giving the format in Grid_ItemDataBound() method..

Data Type of column is varchar.

Hi try this one....
In aspx page
<asp:Label id=Label8 runat="server" Width="80" Text='<%# FormatText((string)DataBinder.Eval(Container, "DataItem.phone")) %>' >

 In the code behind write this function..
public string FormatText(string myText)
        {
            string strPhone = myText.ToString();

            //If the passed string has space or underscore String.Format doesn't work.
            strPhone = strPhone.Replace(" ","");
            strPhone = strPhone.Replace("-","");

            string strFormatedString = String.Format("{0:(###) ###-####}",Int64.Parse (strPhone));
            return strFormatedString;
        }