DataTableCollection.CollectionChanged Event


Occurs after the DataTableCollection is changed because of DataTable objects being added or removed.

Namespace:   System.Data
Assembly:  System.Data (in System.Data.dll)

Public Event CollectionChanged As CollectionChangeEventHandler

For more information about handling events, see NIB: Consuming Events.

The following example demonstrates how to use the CollectionChanged event.

Public Sub TableCollectionCollectionChanged()
    ' create a DataSet with two tables
    Dim dataSet As DataSet = New DataSet()

    AddHandler dataSet.Tables.CollectionChanging, _
        AddressOf Collection_Changed

    ' create Customer table
    Dim custTable As DataTable = New DataTable("Customers")
    custTable.Columns.Add("customerId", _
        System.Type.GetType("System.Integer")).AutoIncrement = True
    custTable.Columns.Add("name", System.Type.GetType("System.String"))
    custTable.PrimaryKey = New DataColumn() {custTable.Columns("customerId")}

    ' create Orders table
    Dim orderTable As DataTable = New DataTable("Orders")
    orderTable.Columns.Add("orderId", _
        System.Type.GetType("System.Integer")).AutoIncrement = True
    orderTable.Columns.Add("customerId", System.Type.GetType("System.Integer"))
    orderTable.Columns.Add("amount", System.Type.GetType("System.Double"))
    orderTable.PrimaryKey = New DataColumn() {orderTable.Columns("orderId")}

    dataSet.Tables.AddRange(New DataTable() {custTable, orderTable})

    ' Now remove all tables.
    ' First check to see if the table can be removed,
    ' then remove it from the collection.
    ' You cannot use a For Each loop when
    ' removing items from a collection.
    Do While (dataSet.Tables.Count > 0)
        Dim table As DataTable = dataSet.Tables(0)
        If (dataSet.Tables.CanRemove(table)) Then
        End If

    Console.WriteLine("dataSet has {0} tables", dataSet.Tables.Count)
End Sub

Private Sub Collection_Changed(ByVal sender As Object, _
    ByVal e As System.ComponentModel.CollectionChangeEventArgs)
    Console.WriteLine("Collection_Changed Event: '{0}'\table element={1}", _
        e.Action.ToString(), e.Element.ToString())
End Sub

.NET Framework
Available since 1.1
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