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
With a project selected in Solution Explorer, click Properties on the Project menu.
Click the Application tab.
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.
To |
See |
|---|---|
Use the events provided by the Visual Basic Application model to run code |
|
Check if the application started with the string /batch as an argument |
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
Project type |
Available |
|---|---|
Windows Application |
Yes |
Class Library |
No |
Console Application |
No |
Windows Control Library |
No |
Web Control Library |
No |
Windows Service |
No |
Web Site |
No |
Permissions
The following permissions may be necessary:
Permission |
Description |
|---|---|
Controls the ability to add an event handler for this event. Associated enumeration: SecurityPermissionFlag.ControlAppDomain. |
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.StartupNextInstance Event
My.Application.CommandLineArgs Property