exception error help

[COMPCAD]

I have this code that I need help with, it does what I need it to do except when I try to remove column 0 it gives me an exception error but when I try to remove any other columns 1-13 it does not give me this error. The error happens on the underlined and bold line. the exact exception that was thrown is :A first chance exception of type 'System NullReferenceException' and when I try to delete column 0 I get this errorbox that says (Object reference not set to an instance of an object)

Private Sub CARD_CATALOGDataGridView_CurrentCellChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles CARD_CATALOGDataGridView.CurrentCellChanged
Dim i As Integer
i = CARD_CATALOGDataGridView.CurrentRow.Index
txtCallnumber.Text = CARD_CATALOGDataGridView.Item(13, i).Value
txtCallnumber.Text = txtCallnumber.Text.Replace(Chr(32), Chr(13) + Chr(10))
End Sub

[JBourgeois]

The code you sent is useless. It does not try to delete a column and does not have the "underlined and bold line".

A NullReferenceException happens when you try to reference an object that has not been initialized. If you get it on tryin to delete Columns(0), it usually means that the grid has not been initialized and is empty.

[COMPCAD]

I am sorry I forgot to underline and put the text in bold that showed the exception error here is that line of code that I was going to underline and make bold:

i = CARD_CATALOGDataGridView.CurrentRow.Index

how would I go about initializing the grid

[JBourgeois]

If the problem is in the CurrentCellChanged, then the grid is already initialized.

Events in the DataGridView are often triggered in strange circumstances.

I suppose that there is no CurrentRow when the event is triggered. This can happen sometimes, such as when you are deleting the last row in the grid.

You can check to make sure that CurrentRow is available before trying to get its index:

Private Sub CARD_CATALOGDataGridView_CurrentCellChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles CARD_CATALOGDataGridView.CurrentCellChanged

    If CARD_CATALOGDataGridView.CurrentRow IsNot Nothing Then

        Dim i As Integer = CARD_CATALOGDataGridView.CurrentRow.Index
        txtCallnumber.Text = CARD_CATALOGDataGridView.Item(13, i).Value
        txtCallnumber.Text = txtCallnumber.Text.Replace(Chr(32), Chr(13) + Chr(10))

    End If

End Sub

[COMPCAD]

Thank You

Just what I was looking for. It works great.

Stephen