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Control.OnDataBinding Method

Raises the DataBinding event.

Namespace:  System.Web.UI
Assembly:  System.Web (in System.Web.dll)

'Declaration
Protected Overridable Sub OnDataBinding ( _
	e As EventArgs _
)

Parameters

e
Type: System.EventArgs

An EventArgs object that contains the event data.

This method notifies a server control to perform any logic for binding data that is associated with it.

If you want to handle the DataBinding event, you should override this event-handling method. This ensures that all delegates attached to the DataBinding event are invoked.

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 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

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1
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