Plan B: Use a little code from VB.
Be sure to add a reference to Microsoft Visual Basic then add this code to your Program.CS file
- /// <summary>
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/// The main entry point for the application.
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/// </summary>
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[STAThread]
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static void Main(string[] commandLine)
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{
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Control.CheckForIllegalCrossThreadCalls = false;
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if (bSplash) SplashScreen.ShowSplashScreen();
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if (bSplash) SplashScreen.SetStatus("Getting Environmental information");
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Application.EnableVisualStyles();
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App myApp = new App();
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myApp.Run(commandLine);
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}
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}
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-
-
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/// <summary>
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/// We inherit from WindowsFormApplicationBase which contains the logic for the application model, including
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/// the single-instance functionality.
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/// </summary>
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class App : Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase
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{
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public App()
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{
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this.IsSingleInstance = true; // makes this a single-instance app
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this.EnableVisualStyles = true; // C# windowsForms apps typically turn this on. We'll do the same thing here.
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this.ShutdownStyle = Microsoft.VisualBasic.ApplicationServices.ShutdownMode.AfterMainFormCloses; // the vb app model supports two different shutdown styles. We'll use this one for the sample.
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}
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/// <summary>
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/// This is how the application model learns what the main form is
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/// </summary>
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protected override void OnCreateMainForm()
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{
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this.MainForm = new Form1();
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}
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-
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/// <summary>
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/// Gets called when subsequent application launches occur. The subsequent app launch will result in this function getting called
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/// and then the subsequent instances will just exit. You might use this method to open the requested doc, or whatever
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/// </summary>
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/// <param name="eventArgs"></param>
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protected override void OnStartupNextInstance(Microsoft.VisualBasic.ApplicationServices.StartupNextInstanceEventArgs eventArgs)
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{
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base.OnStartupNextInstance(eventArgs);
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//System.Windows.Forms.MessageBox.Show("An attempt to launch another instance of this app was made");
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}
-
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}
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You probably want to delete or comment out lines 8 and 9 since they are for a splash screen that won't exist in your project.
