Run Method ()
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Application.Run Method ()

Begins running a standard application message loop on the current thread, without a form.

Namespace: System.Windows.Forms
Assembly: System.Windows.Forms (in

public static void Run ()
public static void Run ()
public static function Run ()
Not applicable.

Exception typeCondition


A main message loop is already running on this thread.

In a Win32-based or Windows Forms application, a message loop is a routine in code that processes user events, such as mouse clicks and keyboard strokes. Every running Windows-based application requires an active message loop, called the main message loop. When the main message loop is closed, the application exits. In Windows Forms, this loop is closed when the Exit method is called, or when the ExitThread method is called on the thread that is running the main message loop.

Most Windows Forms developers will not need to use this version of the method. You should use the Run(Form) overload to start an application with a main form, so that the application terminates when the main form is closed. For all other situations, use the Run(ApplicationContext) overload, which supports supplying an ApplicationContext object for better control over the lifetime of the application.

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0

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