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HierarchicalDataBoundControl.OnDataPropertyChanged Method

  • Reference

Definition

Namespace:
System.Web.UI.WebControls
Assembly:
System.Web.dll

Called when one of the base data source identification properties is changed, to re-bind the data-bound control to its data.

protected:
 override void OnDataPropertyChanged();
protected override void OnDataPropertyChanged ();
override this.OnDataPropertyChanged : unit -> unit
Protected Overrides Sub OnDataPropertyChanged ()

Examples

The following code example demonstrates how a data-bound control can call the OnDataPropertyChanged method if a property that identifies a data source is changed after the data-bound control is initialized. This code example is part of a larger example provided for the HierarchicalDataBoundControl class.

public string DataTextField {
    get {
        object o = ViewState["DataTextField"];
        return((o == null) ? string.Empty : (string)o);
    }
    set {
        ViewState["DataTextField"] = value;
        if (Initialized) {
            OnDataPropertyChanged();
        }
    }
}


Public Property DataTextField() As String
    Get
        Dim o As Object = ViewState("DataTextField")
        If o Is Nothing Then
            Return String.Empty
        Else
            Return CStr(o)
        End If
    End Get
    Set(ByVal value As String)
        ViewState("DataTextField") = value
        If Initialized Then
            OnDataPropertyChanged()
        End If
    End Set
End Property

Remarks

The OnDataPropertyChanged method is called when the DataSource or DataSourceID is changed any time after the page's PreRender event.

Applies to