c# - Get window state of another process

Question

How do I get the window state(maximized, minimized) of another process that's running?

I'd tried by using this:

Process[] procs = Process.GetProcesses();

        foreach (Process proc in procs)
        {

            if (proc.ProcessName == "notepad")
            {
                MessageBox.Show(proc.StartInfo.WindowStyle.ToString());

            }
        }

But if process is Maximized or Minimized,it ever returns Normal.

How to fix this?

Answer 1

You’ll need to use Win32 through P/Invoke for checking the state of another window. Here is some sample code:

static void Main(string[] args)
{
    Process[] procs = Process.GetProcesses();

    foreach (Process proc in procs)
    {
        if (proc.ProcessName == "notepad")
        {
            var placement = GetPlacement(proc.MainWindowHandle);
            MessageBox.Show(placement.showCmd.ToString());
        }
    }
}

private static WINDOWPLACEMENT GetPlacement(IntPtr hwnd)
{
    WINDOWPLACEMENT placement = new WINDOWPLACEMENT();
    placement.length = Marshal.SizeOf(placement);
    GetWindowPlacement(hwnd, ref placement);
    return placement;
}

[DllImport("user32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
internal static extern bool GetWindowPlacement(
    IntPtr hWnd, ref WINDOWPLACEMENT lpwndpl);

[Serializable]
[StructLayout(LayoutKind.Sequential)]
internal struct WINDOWPLACEMENT
{
    public int length;
    public int flags;
    public ShowWindowCommands showCmd;
    public System.Drawing.Point ptMinPosition;
    public System.Drawing.Point ptMaxPosition;
    public System.Drawing.Rectangle rcNormalPosition;
}

internal enum ShowWindowCommands : int
{
    Hide = 0,
    Normal = 1,
    Minimized = 2,
    Maximized = 3,
}

Definition courtesy of pinvoke.net.