hatem72
asked on
DataGridViewComboBoxColumn Error (Object reference not set to an instance of an object)
Hi,
VB 2005, Windows Forms
Here is my code:
Dim nColCombo1 As New DataGridViewComboBoxColumn
With nColCombo1
.HeaderText = "Item"
.Name = "Col_ItemID"
Dim x As String = MyItem.FillItemsGrid(nColC
dataGridView1.Columns.Add(
End With
In my class :
Public Function FillItemsGrid(ByRef cBox As Object, Optional ByVal ProvId As Integer = 0) As String
Dim Sqls As String
...
My Problem is the error was rised when calling the function ( Object reference not set to an instance of an object . )
Thanx in advance
VB 2005, Windows Forms
Here is my code:
Dim nColCombo1 As New DataGridViewComboBoxColumn
With nColCombo1
.HeaderText = "Item"
.Name = "Col_ItemID"
Dim x As String = MyItem.FillItemsGrid(nColC
dataGridView1.Columns.Add(
End With
In my class :
Public Function FillItemsGrid(ByRef cBox As Object, Optional ByVal ProvId As Integer = 0) As String
Dim Sqls As String
...
My Problem is the error was rised when calling the function ( Object reference not set to an instance of an object . )
Thanx in advance
I think your problem might be with passing a reference type (object) by reference. Almost always an object should be passed by the default ByVal. You will still be able to change the properties of the object, since ByVal passes a copy of the pointer to the object and not the actual pointer to the object (for reference types such as objects). The danger of passing the original pointer to the object, (ByRef) if not needed is that the method can replace the object with a different instance, which is what I think may be happening.
ASKER
First thank u ... i did try to change ByRef -> ByVal BUT Same Problem
ok is there any way to pass DataGridViewComboBoxColumn
instead of my way
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ASKER
Yes Sancler ... MyItem class works fine and there is many functions and subs and all works fine.
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ASKER
Hi
Sancler u r right about the problem ... i am sure that is the class is fine but i dont know
how do i miss the NEW keyword ... after ur post i copy the function form the class
to the form and it works ... so i found where the problem is .
lorelogic thank u for ur help ... SORYY there is just 500p to split .