'Declaration
 
Protected Overridable Sub OnItemAdding( _
   ByVal item As ColumnBase _
) 

'Usage
 
Dim instance As ObservableColumnCollection
Dim item As ColumnBase
 
instance.OnItemAdding(item)

protected virtual void OnItemAdding( 
   ColumnBase item
)

Parameters

item

Target Platforms: Windows 11, Windows 10, Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

ObservableColumnCollection Class
ObservableColumnCollection Members