WindowsFormsApplicationBase.Startup Event


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Occurs when the application starts.

Namespace:   Microsoft.VisualBasic.ApplicationServices
Assembly:  Microsoft.VisualBasic (in Microsoft.VisualBasic.dll)

public event StartupEventHandler Startup

A normal (non-single-instance) application raises the Startup event every time it starts. A single-instance application raises the Startup event when it starts only if the application is not already active; otherwise, it raises the StartupNextInstance event. For more information, see StartupNextInstance.

This event is part of the Visual Basic Application model. For more information, see Overview of the Visual Basic Application Model.

You can use the Cancel property of the e parameter to control the loading of an application's startup form. When the Cancel property is set to True, the startup form does not start. In that case, your code should call an alternate startup code path.

You can use the CommandLine property of the e parameter or the CommandLineArgs property to access the application's command-line arguments.

The code for the Startup event handler is stored in the ApplicationEvents.vb file, which is hidden by default.

To access the Code Editor window for application events

  1. With a project selected in Solution Explorer, click Properties on the Project menu.

  2. Click the Application tab.

  3. Click the View Application Events button to open the Code Editor.

For more information, see Application Page, Project Designer (Visual Basic).

Project type


Windows Forms Application


Class Library


Console Application


Windows Forms Control Library


Web Control Library


Windows Service


Web Site


This example uses the My.Application.SplashScreen property and the My.Application.Startup event to update the splash screen with status information as the application starts.

Private Sub MyApplication_Startup( 
    ByVal sender As Object, 
    ByVal e As Microsoft.VisualBasic.ApplicationServices.StartupEventArgs 
) Handles Me.Startup
    ' Get the splash screen.
    Dim splash As SplashScreen1 = CType(My.Application.SplashScreen, SplashScreen1)
    ' Display current status information.
    splash.Status = "Current user: " & My.User.Name
End Sub

This example requires that the project have a splash screen named SplashScreen1. The splash screen needs to have property named Status that updates its user interface.

You must enter the code in the Code Editor window for application events. To access this window, follow the instructions from this topic's Remarks section. For more information, see Application Page, Project Designer (Visual Basic).


Controls the ability to add an event handler for this event. Associated enumeration: SecurityPermissionFlag.ControlAppDomain.

.NET Framework
Available since 2.0
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