Application.MessageLoop Property  
Definition
Important
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Gets a value indicating whether a message loop exists on this thread.
public:
 static property bool MessageLoop { bool get(); };public static bool MessageLoop { get; }static member MessageLoop : boolPublic Shared ReadOnly Property MessageLoop As BooleanProperty Value
true if a message loop exists; otherwise, false.
Remarks
When hosting Windows Forms in other environments, such as unmanaged applications, this property will always return false. Use RegisterMessageLoop to instruct Windows Forms if the hosting environment still has an active message loop.