Pop up main Window using Win32API

Visual Basic .NET » Windows Forms

Pop up main Window using Win32API -- Joe --

I need only one instance of a Windows app running and also pop up its main form when the user double click the desktop shortcut (executable).

See the code below:

<code>
using System;
using System.Collections.Generic;
using System.Windows.Forms;
using System.ServiceProcess;
using System.Diagnostics;
using System.Net;
using System.Runtime.InteropServices;

namespace MyNamespace
{
public class MyClass
{
public enum ShowWindow
{
SW_HIDE = 0,
SW_SHOWNORMAL = 1,
SW_NORMAL = 1,
SW_SHOWMINIMIZED = 2,
SW_SHOWMAXIMIZED = 3,
SW_MAXIMIZE = 3,
SW_SHOWNOACTIVATE = 4,
SW_SHOW = 5,
SW_MINIMIZE = 6,
SW_SHOWMINNOACTIVE = 7,
SW_SHOWNA = 8,
SW_RESTORE = 9,
SW_SHOWDEFAULT = 10,
SW_FORCEMINIMIZE = 11,
SW_MAX = 11
}

private static void Main()
{
Process

launchedProcesses =
Process.GetProcessesByName(Process.GetCurrentProcess().ProcessName);
if (launchedProcesses.Length > 1)
{
// need to pop up window here
RestoreWindow(launchedProcesses

.MainWindowHandle);
return;
}

Application.Run(new frmMain());
}

public static void RestoreWindow(IntPtr handle)
{
API.ShowWindowAsync(handle, (int)ShowWindow.SW_SHOWNORMAL);
API.SetForegroundWindow(handle).ToString();
}
}

public static class API
{

public static extern bool ShowWindowAsync(IntPtr hWnd, int nCmdShow);

public static extern bool SetForegroundWindow(IntPtr hWnd);
}
}
</code>

Everything is working but a little strangely. Sometime the window pop up sometime not. Also when I set the property ShowInTaskBar of the main form to false (because it is minimized to system tray) the code do not work at all.

Help please!!!!

-- Tito --

You can use the system.process class to determine if the application is running or not. If you do find it running, you can either kill it or switch to it.

-- Joe --

Tito, can I switch to it and pop up its main window up? I will try to do it with that Process class.

-- JamieFraser --

You can't do that with the process class.

Have a look on google / codeproject for "single instance app" or something like that. Or if you are using .NET 2.0, you can set a setting in the project to ensure that only one instance of the app can run at a time.

On 18/07/06, Joe <jonathanpoulin> wrote:

Tito, can I switch to it and pop up its main window up? I will try to
do it with that Process class.
>

-- Joe --

Thanks!

For the option is VS2005 I can't find it. Any advise?

Thanks again man!
Joe.

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