Control.OnDataBinding(EventArgs) Control.OnDataBinding(EventArgs) Control.OnDataBinding(EventArgs) Control.OnDataBinding(EventArgs) Method

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 EventArgs EventArgs 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、上書きする方法、OnDataBinding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メソッド。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

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

処理する場合、DataBindingイベントでは、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、すべてのデリゲートに接続されている、DataBindingイベン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