My.Application.Startup Event

Occurs when the application starts.

' Usage
Public Sub Me_Startup( _
   ByVal sender As Object, _
   ByVal e As StartupEventArgs _
) Handles Me.Startup
End Sub
' Declaration
Public Event Startup( _
   ByVal sender As Object, _
   ByVal e As StartupEventArgs _
)

Parameters

• sender
  The Object that raised the event.

• e
  A StartupEventArgs object that contains the application's command-line arguments.

Remarks

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 My.Application.StartupNextInstance Event and How to: Specify Instancing Behavior for an Application (Visual Basic).

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. For example, see How to: Enable a Batch Mode for Window Forms Applications.

You can use the CommandLine property of the e parameter or the My.Application.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 How to: Handle Application Events (Visual Basic).

Tasks

The following table lists examples of tasks involving the My.Application.Startup event.

Example

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 How to: Handle Application Events (Visual Basic).

Requirements

Namespace:Microsoft.VisualBasic.ApplicationServices

Class:WindowsFormsApplicationBase

Assembly: Visual Basic Runtime Library (in Microsoft.VisualBasic.dll)

Availability by Project Type

Permissions

The following permissions may be necessary:

For more information, see Code Access Security and Requesting Permissions.

See Also

Tasks

How to: Enable a Batch Mode for Window Forms Applications

How to: Handle Application Events (Visual Basic)

How to: Specify Instancing Behavior for an Application (Visual Basic)

Concepts

Overview of the Visual Basic Application Model

Reference

My.Application Object

My.Application.StartupNextInstance Event

My.Application.CommandLineArgs Property

Microsoft.VisualBasic.ApplicationServices.StartupEventArgs

WindowsFormsApplicationBase.Startup