DataColumnCollection.CollectionChanged Event

Definition

Occurs when the columns collection changes, either by adding or removing a column.

public event System.ComponentModel.CollectionChangeEventHandler CollectionChanged;

Examples

The following example adds an event handler for the CollectionChanged event.

private void AddEventHandler(DataTable table)
{
    DataColumnCollection columns = table.Columns;
    columns.CollectionChanged += new 
        System.ComponentModel.CollectionChangeEventHandler(
        ColumnsCollection_Changed);
}

private void ColumnsCollection_Changed(object sender, 
    System.ComponentModel.CollectionChangeEventArgs e)
{
    DataColumnCollection columns = 
        (DataColumnCollection) sender;
    Console.WriteLine("ColumnsCollectionChanged: " 
        + columns.Count);
}
 Private Sub AddEventHandler(table As DataTable)
     Dim columns As DataColumnCollection = table.Columns
     AddHandler columns.CollectionChanged, _
        AddressOf ColumnsCollection_Changed
 End Sub    
    
 Private Sub ColumnsCollection_Changed _
    (sender As Object, e As System.ComponentModel. _
    CollectionChangeEventArgs)

     Dim columns As DataColumnCollection = _
        CType(sender, DataColumnCollection)
     Console.WriteLine("ColumnsCollectionChanged: " _
        & columns.Count.ToString())
End Sub

Remarks

Use the Contains and CanRemove methods to determine whether a column exists and can be removed.