Export (0) Print
Expand All

ListControlDataBindingHandler Class

Performs data binding of a ListControl Web server control within a visual designer.


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

<SecurityPermissionAttribute(SecurityAction.Demand, Flags := SecurityPermissionFlag.UnmanagedCode)> _
Public Class ListControlDataBindingHandler _
	Inherits DataBindingHandler

The ListControlDataBindingHandler type exposes the following members.

Public methodListControlDataBindingHandlerInfrastructure. Initializes a new instance of the ListControlDataBindingHandler class.

Public methodDataBindControlPerforms data binding on the specified control. (Overrides DataBindingHandler.DataBindControl(IDesignerHost, Control).)
Public methodEquals(Object)Determines whether the specified object is equal to the current object. (Inherited from Object.)
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodGetHashCodeServes as the default hash function. (Inherited from Object.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)

The ListControlDataBindingHandler class performs design-time data binding of a ListControl control. The ListControlDataBindingHandler class is referenced by the ListControl using the DataBindingHandlerAttribute class.

The DataBindControl method performs the design-time data binding.

This section contains two code examples. The first one demonstrates how to derive a control from the RadioButtonList control and associate it with its data binding handler. The second one demonstrates how to the derive a class from the ListControlDataBindingHandler class.

The following code example shows how to derive the SimpleRadioButtonList control from the RadioButtonList control, and then apply the DataBindingHandlerAttribute attribute to associate the SimpleRadioButtonList control with its data binding handler, the SimpleRadioButtonListDataBindingHandler class.

Imports System.Web
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.ComponentModel
Imports System.Security.Permissions

Namespace Examples.VB.WebControls.Design

    ' The SimpleRadioButtonList is a copy of the RadioButtonList. 
    ' It uses the SimpleRadioButtonListDesigner for design-time support.
    <AspNetHostingPermission(SecurityAction.Demand, _
        Level:=AspNetHostingPermissionLevel.Minimal)> _
    <AspNetHostingPermission(SecurityAction.InheritanceDemand, _
        Level:=AspNetHostingPermissionLevel.Minimal)> _
    <DesignerAttribute(GetType(Examples.VB.WebControls.Design. _
        SimpleRadioButtonListDesigner))> _
    <DataBindingHandler(GetType(Examples.VB.WebControls.Design. _
        SimpleRadioButtonListDataBindingHandler))> _
    Public Class SimpleRadioButtonList
        Inherits RadioButtonList
    End Class ' SimpleRadioButtonList
End Namespace ' Examples.VB.WebControls.Design

The following code example shows how to derive the SimpleRadioButtonListDataBindingHandler class from the ListControlDataBindingHandler class. It overrides the DataBindControl method to add a message to the associated SimpleRadioButtonList control when that control is data bound.

' Imports System.Design 
Imports System
Imports System.ComponentModel
Imports System.ComponentModel.Design
Imports System.Web.UI
Imports System.Web.UI.Design.WebControls

Namespace Examples.VB.WebControls.Design

    ' Derive the SimpleRadioButtonListDataBindingHandler. 
    Public Class SimpleRadioButtonListDataBindingHandler
        Inherits ListControlDataBindingHandler

        ' Override the DataBindControl. 
        Public Overrides Sub DataBindControl( _
        ByVal designerHost As IDesignerHost, _
        ByVal control As Control)

            ' Create a reference, named dataSourceBinding, 
            ' to the control's DataSource binding. 
            Dim dataSourceBinding As DataBinding _
                = CType( _
                control, _

            ' If the binding exists, create a reference to the 
            ' list control, clear its ListItemCollection, and then add 
            ' an item to the collection. 
            If Not (dataSourceBinding Is Nothing) Then 
                Dim simpleControl As SimpleRadioButtonList = _
                    CType(control, SimpleRadioButtonList)

                simpleControl.Items.Add("Data-bound Radio Button.")
            End If 
        End Sub ' DataBindControl
    End Class ' SimpleRadioButtonListDataBindingHandler
End Namespace ' Examples.VB.WebControls.Design

.NET Framework

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

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
© 2015 Microsoft