static void ComputeRectRelativeToParent(IntPtr hWnd, IntPtr hwndParent, out PInvoke.RECT clientParent, out PInvoke.RECT client)
{
PInvoke.RECT rw, rc;
PInvoke.GetWindowRect(hWnd, out rw);
PInvoke.GetClientRect(hWnd, out rc);
PInvoke.RECT rpw, rpc;
PInvoke.GetWindowRect(hwndParent, out rpw);
PInvoke.GetClientRect(hwndParent, out rpc);
PInvoke.POINT p0 = new PInvoke.POINT()
{
X = rw.Left,
Y = rw.Top
};
PInvoke.ScreenToClient(hwndParent, ref p0);
PInvoke.POINT p1 = new PInvoke.POINT()
{
X = rw.Right,
Y = rw.Bottom
};
PInvoke.ScreenToClient(hwndParent, ref p1);
clientParent = rpc;
client = new PInvoke.RECT()
{
Left = p0.X,
Top = p0.Y,
Right = p1.X,
Bottom = p1.Y
};
}
public static bool ElementVisibleOnScreen(IntPtr hWnd)
{
IntPtr hdc = PInvoke.GetDC(hWnd);
PInvoke.RECT r;
var cb = PInvoke.GetClipBox(hdc, out r);
var flag = false;
switch ((PInvoke.ClipBoxComplexity)cb)
{
case PInvoke.ClipBoxComplexity.NullRegion:
Console.WriteLine("window covered completely");
flag = false;
break;
case PInvoke.ClipBoxComplexity.Error:
Console.WriteLine("error: {0]", Marshal.GetLastWin32Error());
flag = false;
break;
case PInvoke.ClipBoxComplexity.SimpleRegion:
PInvoke.RECT rcClient;
PInvoke.GetClientRect(hWnd, out rcClient);
if (rcClient.Left == r.Left && rcClient.Top == r.Top && rcClient.Right == r.Right && rcClient.Bottom == r.Bottom)
{
Console.WriteLine("completely uncovered");
flag = true;
}
else
{
Console.WriteLine("partially covered");
flag = false;
}
break;
case PInvoke.ClipBoxComplexity.ComplexRegion:
Console.WriteLine("partially covered");
flag = false;
break;
default:
Console.WriteLine("unknown return code {0}", cb);
flag = false;
break;
}
PInvoke.ReleaseDC(hWnd, hdc);
return(flag);
}
