Assembly: System.Web (in system.web.dll)
Using the capabilities of the Web Parts control set, it is possible to create a connection between two WebPart or other server controls, with one control acting as the provider, and the other acting as the consumer of data. To form a connection, the two controls must reside in a zone that inherits from the WebPartZoneBase class (such as the WebPartZone control), and they must be designed correctly to share data through a common interface. For details about Web Parts connections, see WebPartConnection and Web Parts Connections Overview.
The WebPartConnectionsEventArgs class passes event data to methods that use the WebPartConnectionsEventHandler delegate to handle events. There are two such connection-related methods that raise events and use the WebPartConnectionsEventArgs class to provide event data. Both are members of the WebPartManager control. The OnWebPartsConnected method raises the WebPartsConnected event after two server controls have successfully connected, and the OnWebPartsDisconnected method raises the WebPartsDisconnected event after two server controls have been disconnected.
Developers can create custom event handler methods for the WebPartsConnected and WebPartsDisconnected events, and in those methods, they can use the WebPartConnectionsEventArgs class to access details of a connection. For example, a developer can declare the OnWebPartsConnected attribute on the <asp:webpartmanager> element, and assign to it a custom method name that will handle the event. In the custom handler method, developers can access the details of a connection by using the WebPartConnectionsEventArgs object that is passed to the method as a parameter.
The WebPartConnectionsEventArgs class has two overloads of the constructor. The System.Web.UI.WebControls.WebParts.WebPartConnectionsEventArgs(WebPart,ProviderConnectionPoint,WebPart,ConsumerConnectionPoint) constructor is the default; it initializes the property values for the class. The System.Web.UI.WebControls.WebParts.WebPartConnectionsEventArgs(WebPart,ProviderConnectionPoint,WebPart,ConsumerConnectionPoint,WebPartConnection) constructor calls the default constructor, and then it also initializes the Connection property.
The WebPartConnectionsEventArgs class has several properties, all of which refer to the essential aspects of a Web Parts connection. The Connection property refers to the associated WebPartConnection object that represents the entire connection. The Provider property references a WebPart or other server control acting as the provider in the connection, and the Consumer property references a WebPart or server control acting as the consumer. The ProviderConnectionPoint property references the connection's ProviderConnectionPoint object, while the ConsumerConnectionPoint property references the ConsumerConnectionPoint object.