Control.OnDataBinding(EventArgs) メソッド

定義

DataBinding イベントを発生させます。Raises the DataBinding event.

protected:
 virtual void OnDataBinding(EventArgs ^ e);
protected virtual void OnDataBinding (EventArgs e);
abstract member OnDataBinding : EventArgs -> unit
override this.OnDataBinding : EventArgs -> unit
Protected Overridable Sub OnDataBinding (e As EventArgs)

パラメーター

e
EventArgs

イベント データを格納している EventArgs オブジェクト。An EventArgs object that contains the event data.

次の例では、OnDataBinding メソッドをオーバーライドして、データソースから親コントロールに子コントロールを追加する方法を示します。The following example demonstrates how to override the OnDataBinding method to add child controls to the parent control from a data source.

// Override to create the repeated items from the DataSource.
protected override void OnDataBinding(EventArgs e) {
    base.OnDataBinding(e);

    if (DataSource != null) {
        // Clear any existing child controls.
        Controls.Clear();
        // Clear any previous view state for the existing child controls.
        ClearChildViewState();

        // Iterate over the DataSource, creating a new item for each data item.
        IEnumerator dataEnum = DataSource.GetEnumerator();
        int i = 0;
        while(dataEnum.MoveNext()) {

            // Create an item.
            RepeaterItem item = new RepeaterItem(i, dataEnum.Current);
            // Initialize the item from the template.
            ItemTemplate.InstantiateIn(item);
            // Add the item to the ControlCollection.
            Controls.Add(item);

            i++;
        }

        // Prevent child controls from being created again.
        ChildControlsCreated = true;
        // Store the number of items created in view state for postback scenarios.
        ViewState["NumItems"] = i;
    }
}
' Override to create the repeated items from the DataSource.
Protected Overrides Sub OnDataBinding(E As EventArgs)
    MyBase.OnDataBinding(e)

    If Not DataSource Is Nothing
        ' Clear any existing child controls.
        Controls.Clear()
        ' Clear any previous view state for the existing child controls.
        ClearChildViewState()

        ' Iterate over the DataSource, creating a new item for each data item.
        Dim DataEnum As IEnumerator = DataSource.GetEnumerator()
        Dim I As Integer = 0
        Do While (DataEnum.MoveNext())

            ' Create an item.
            Dim Item As RepeaterItemVB = New RepeaterItemVB(I, DataEnum.Current)
            ' Initialize the item from the template.
            ItemTemplate.InstantiateIn(Item)
            ' Add the item to the ControlCollection.
            Controls.Add(Item)

            I = I + 1
        Loop

        ' Prevent child controls from being created again.
        ChildControlsCreated = true
        ' Store the number of items created in view state for postback scenarios.
        ViewState("NumItems") = I
    End If
End Sub

注釈

このメソッドは、サーバーコントロールに関連付けられているデータをバインドするためのロジックを実行するように通知します。This method notifies a server control to perform any logic for binding data that is associated with it.

DataBinding イベントを処理する場合は、このイベント処理メソッドをオーバーライドする必要があります。If you want to handle the DataBinding event, you should override this event-handling method. これにより、DataBinding イベントにアタッチされたすべてのデリゲートが呼び出されます。This ensures that all delegates attached to the DataBinding event are invoked.

適用対象

こちらもご覧ください