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WebPart.EnsureInterfaces method

NOTE: This API is now obsolete.

Provides notification for a connectable Web Part that it should ensure all its interfaces are registered using the RegisterInterface method.

Namespace:  Microsoft.SharePoint.WebPartPages
Assembly:  Microsoft.SharePoint (in Microsoft.SharePoint.dll)

'Declaration
<ObsoleteAttribute("Use ConnectionProvider or ConnectionConsumer attribute to create ConnectionPoint instead.")> _
Public Overridable Sub EnsureInterfaces
'Usage
Dim instance As WebPart

instance.EnsureInterfaces()

When developing a connectable Web Part you must override the EnsureInterfaces method. Overriding this method is not necessary when you are developing a Web Part that does not support connections.

The following code example shows an overridden EnsureInterfaces method. This code example is part of a larger example provided for the ICellProvider interface.

For an overview of the steps of creating a connectable Web Part, see Creating a Connectable Web Part.

' Step #4: Override the EnsureInterfaces() method and call the RegisterInterface method.
Public Overrides Sub EnsureInterfaces()
    ' If your Web Part is installed in the bin directory and the Code Access Security (CAS) setting doesn't 
    ' allow Web Part Connections, an exception will be thrown. To allow your Web Part to behave 
    ' well and continue working, a try/catch block should be used when attempting to register interfaces.
    ' Web Part Connections will only work if the level attribute of the <trust> tag in the 
    ' web.config file is set to WSS_Minimal, WSS_Medium, or Full. By default a new SharePoint site
    ' is installed with the trust level set to WSS_Minimal.
    Try
        ' Register the ICellProvider Interface
        ' <param name="interfaceName">Friendly name of the interface that is being implemented.
        ' It must be unique on the client so the _WPQ_ token is used.</param>
        ' <param name="interfaceType">Specifies which interface is being implemented.</param>
        ' <param name="maxConnections">Defines how many times this interface can be connected.</param>
        ' <param name="runAtOptions">Determines where the interface can run.</param>
        ' <param name="interfaceObject">Reference to the object that is implementing this interface.</param>
        ' <param name="interfaceClientReference">Name used to reference the interface on the client. 
        ' It must be unique on the client so the _WPQ_ token is used.</param>
        ' <param name="menuLabel">Label for the interface which appears in the UI</param>
        ' <param name="description">Description of the interface which appears in the UI</param>
        ' <param name="allowCrossPageConnection">Specifies if the interface can connect to a Web Part
        ' on a different page. This is an optional parameter with a default of false. Note that only some 
        ' server side interfaces are allowed to connect across pages by the Web Part infrastructure. 
        ' The ICellProvider interface is not allowed to connect across pages.</param>
        RegisterInterface("MyCellProviderInterface_WPQ_", InterfaceTypes.ICellProvider, WebPart.UnlimitedConnections, ConnectionRunAt.Server, Me, "CellProviderInterface_WPQ_", "Provide Cell To", "Provides a single value to a cell consumer Web Part.") 'Description - MenuLabel - InterfaceClientReference - InterfaceObject - RunAtOptions - MaxConnections - InterfaceType - InterfaceName
    Catch se As SecurityException
        _registrationErrorOccurred = True
    End Try
End Sub

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