Visual Basic 2005 in a Nutshell (In a Nutshell (OReilly))

2017-07-07 02:10:07

StartupNextInstance Event

Location

My.Application.StartupNextInstance

Syntax

Public Sub Me_StartupNextInstance(ByVal sender As Object, _ ByVal e As StartupNextInstanceEventArgs) _ Handles Me.StartupNextInstance End Sub

sender (required; Object): The object that raised the event
e (required; StartupEventArgs): An event parameter that contains information about the command-line arguments, using the Microsoft.VisualBasic.ApplicationServices.StartupEventArgs class

Description

The StartupNextInstance event occurs in single-instance applications when subsequent instances of the application begin. The initial use of the application fires the Startup event, not the StartupNextInstance event. Non-single-instance applications never call the StartupNextInstance event.

Public Members

The e argument to this event, as an instance of the StartupEventArgs class, includes the following notable public members.

Member	Description
`Cancel`	Property. Setting this `Boolean` value to `true` causes the newly initiated instance of the application to exit without continuing.
`CommandLine`	Property. A collection of the command-line arguments used to start this specific instance of the application. The application path itself is not one of the collection members; the first member is the first true argument. Do not use the My.Application.CommandLineArgs property, as that only includes the arguments for the initial instance.

Usage at a Glance

This event is only available in Windows Forms applications.

This event handler can be found in the ApplicationEvents.vb source code file for your project. This file is normally hidden, but it can be viewed by toggling the Show All Files button in the Solution Explorer window in Visual Studio.

Applications are multi-instance by default. To set an application as single-instance, alter the project's Application Properties, setting the "Make single instance application" field.

Example

The StartupNextInstance event's code appears in the ApplicationEvents.vb file in a Windows Forms application.

Namespace My Class MyApplication Private Sub MyApplication_StartupNextInstance( _ ByVal sender As Object, ByVal e As _ Microsoft.VisualBasic.ApplicationServices. _ StartupNextInstanceEventArgs) _ Handles Me.StartupNextInstance Console.WriteLine("I'm already running!") End Sub End Class End Namespace

Related Framework Entries

Microsoft.VisualBasic.ApplicationServices.StartupEventArgs Class

Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.StartupNextInstance Event