Check if a window is focused

Question

I'm making a c# overlay for a game. It appears on the game but it won't hide if the game is minimized so I'm wondering if there's any way to check if a window is minimized/out of focus. I searched about it on google but I couldn't find anything useful.

[Chcek this for lost focus](https://stackoverflow.com/questions/570021/forms-lost-focus-in-c-sharp/570045) I think it will be help full — Avinash Reddy, Apr 15 '19 at 05:15
No no, I'm checking for a if a window is focused, not a form. — RageRBoy, Apr 15 '19 at 05:17
(form is minimized)[https://stackoverflow.com/questions/1052913/how-to-detect-when-a-windows-form-is-being-minimized] — Avinash Reddy, Apr 15 '19 at 05:27
are you talking about an MDI container? what exactly do you mean by window? — Mong Zhu, Apr 15 '19 at 05:35
so basically you want to find out whether there is another application window is topmost ? — Mong Zhu, Apr 15 '19 at 06:09
would [this post](https://stackoverflow.com/questions/35315788/how-do-i-get-the-topmost-status-of-every-window-in-c-sharp) be of any help ? — Mong Zhu, Apr 15 '19 at 06:52

score 2 · Answer 1 · answered Apr 15 '19 at 10:39

To check the state of a window (normal, maximized or minimized) when you have the windows caption name or the windows handle, you can use this code:

[DllImport("user32.dll", SetLastError = true)]
static extern IntPtr FindWindow(string lpClassName, string lpWindowName);

[DllImport("user32.dll")]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool IsIconic(IntPtr hWnd);

[DllImport("user32.dll")]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool IsZoomed(IntPtr hWnd);

enum WinState
{
    None,
    Maximized,
    Minimized,
    Normal,
}

private static WinState GetWindowState(IntPtr hWnd)
{
    WinState winState = WinState.None;
    if (hWnd != IntPtr.Zero)
    {
        if (IsIconic(hWnd))
        {
            winState = WinState.Minimized;
        }
        else if (IsZoomed(hWnd))
        {
            winState = WinState.Maximized;
        }
        else
        {
            winState = WinState.Normal;
        }
    }

    return winState;
}

private static WinState GetWindowState(string windowCaption)
{
    return GetWindowState((IntPtr)FindWindow(null, windowCaption));
}

Usage:

string windowCaption = "New Tab - Google Chrome";
WinState winState = GetWindowState(windowCaption);

Check if a window is focused

1 Answers1