I'm using an ObjectDataSource to bind an object to a GridView. In the OnRowDataBound event handler I'm trying to determine if a certain button should be visible or not. When the runtime encounters this statement it fires an "No default member found for type 'Pledge'." error:

lbDel.Visible = Not (e.Row.DataItem("BillingReady"))

My Object class that is bound to the GridView:

public class Pledges : System.Collections.CollectionBase
{
    public Pledge this[int index]
    {
        get { return ((Pledge)(List[index])); }
        set { List[index] = value; }
    }

    public int Add(Pledge pledge)
    {
        return List.Add(pledge);
    }
}

My Pledge class:

public class Pledge
{
    public int PledgeID { get; set; }
    public int EventID { get; set; }
    public int SponsorID { get; set; }
    public int StudentID { get; set; }
    public decimal Amount { get; set; }
    public string Type { get; set; }
    public bool IsPaid { get; set; }
    public string EventName { get; set; }
    public DateTime EventDate { get; set; }
    public bool BillingReady { get; set; }
    public string SponsorName { get; set; }
    public int Grade_level { get; set; }
    public string StudentName { get; set; }
    public string NickName { get; set; }
    public int Laps { get; set; }
    public decimal PledgeSubtotal { get; set; }
}

My OnRowDataBound event handler:

Protected Sub PledgeGrid_OnRowDataBound(ByVal sender As Object, ByVal e As GridViewRowEventArgs)
    If (e.Row.RowType = DataControlRowType.DataRow) And _
      Not ((e.Row.RowState = DataControlRowState.Edit) Or ((e.Row.RowState = DataControlRowState.Alternate) And (e.Row.RowState = DataControlRowState.Edit))) Then
        Dim lbDel As LinkButton
        Dim lbEd As LinkButton
        lbDel = CType(e.Row.FindControl("lbDelete"), LinkButton)
        lbEd = CType(e.Row.FindControl("lbEdit"), LinkButton)

        If ((e.Row.RowState = DataControlRowState.Normal) Or (e.Row.RowState = DataControlRowState.Alternate)) Then
            lbDel.Visible = Not (e.Row.DataItem("BillingReady"))    '<-- Problem happens here
            lbEd.Visible = Not (e.Row.DataItem("BillingReady"))
        End If
    End If
End Sub

Yes, I'm having to mix VB and C# but I don't think that's the problem. If I understand the C# equivalent of a VB Default Property is called an indexer. Shouldn't this qualify as an indexer?

public Pledge this[int index]
{
    get { return ((Pledge)(List[index])); }
    set { List[index] = value; }
}

• c#
• vb.net
• gridview

Try to cast the DataItem to Pledge:

Dim pledge = DirectCast(e.Row.DataItem, Pledge)
lbDel.Visible = Not pledge.BillingReady

I had this same problem when binding a c# model to a VB DataGrid.

Normally in the aspx file, the DataGrid would display a field in a template column with:

        <asp:templatecolumn headertext="Reference">
            <itemtemplate>
                <%# Container.DataItem("Reference")%>
            </itemtemplate>
        </asp:templatecolumn>

But when using my c# model, the DataGrid needs a template column syntax of:

        <asp:templatecolumn headertext="Reference">
            <itemtemplate>
                <%# DataBinder.Eval(Container.DataItem, "Reference") %>
            </itemtemplate>
        </asp:templatecolumn>

This was a confusing issue so hopefully the answer will help you save the hour it took me to figure this out.