Provides a generic dispatcher helper to ensure that a method is invoked on the application's main thread.
Assembly: Microsoft.VisualStudio.Shell.10.0 (in Microsoft.VisualStudio.Shell.10.0.dll)
Thetype exposes the following members.
|Equals||Determines whether the specified Object is equal to the current Object. (Inherited from Object.)|
|Finalize||Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)|
|GetHashCode||Serves as a hash function for a particular type. (Inherited from Object.)|
|GetInvocationWrapper||Gets the invocation wrapper.|
|GetType||Gets the Type of the current instance. (Inherited from Object.)|
|Invoke(Action)||Calls an action on the UI thread.|
|Invoke(Of TResult)(Func(Of TResult))|
|MemberwiseClone||Creates a shallow copy of the current Object. (Inherited from Object.)|
|ToString||Returns a string that represents the current object. (Inherited from Object.)|
We use the current application's dispatcher for convenient identification of the main thread. Note that this means that the application object must be initialized by the window manager.
However, DispatcherOperation objects are not used, because they are not compatible with RPC. For example, if the UI thread is in the middle of an RPC call, and code must run on the UI thread, then DispatcherOperation objects will not get through. This is because DispatcherOperation objects are initiated by posting a message to the UI thread, and the UI thread must dispatch that message. If the UI thread is making an RPC call, these messages will not be removed from the queue. The standard OLE message filter processes only a limited set of messages from the queue.
By going through the service, the operation becomes a COM call on the UI thread. This operation is allowed through the Visual Studio message filter if it is part of the same logical call, since the message filter will see it as a nested call and may not reject it.