确定窗口是否在最顶层

Question

I am able to set a windows position as topmost and also setting it no topmost with SetWindowPos . But i can't figure out how to check if a window is topmost or not. Is there any Method to check if a window is topmost or not with pinvoke?

Answer 1

You can use the GetWindowLong() function to check the Extended Window Styles .

Untested, but I believe it should work:

[DllImport("user32.dll", SetLastError=true)]
static extern int GetWindowLong(IntPtr hWnd, int nIndex);

const int GWL_EXSTYLE = -20;
const int WS_EX_TOPMOST = 0x0008;

public static bool IsWindowTopMost(IntPtr hWnd)
{
    int exStyle = GetWindowLong(hWnd, GWL_EXSTYLE);
    return (exStyle & WS_EX_TOPMOST) == WS_EX_TOPMOST;
}

Answer 2

Depending on the UI technology you*re using, you can choose of the following two:

• Windows Forms: Form.TopMost
• WPF: Window.TopMost

You can you those properties to check if a certain window is topmost and you can also use these to set a window topmost. I'd prefer these in favor of any win32 methods.