public bool ModifyStyleEx(PInvokeWindows.SetWindowLongFlags dwRemove, PInvokeWindows.SetWindowLongFlags dwAdd) { int GWL_STYLE = -16; PInvokeWindows.SetWindowLongFlags dwStyle = (PInvokeWindows.SetWindowLongFlags)PInvokeWindows.GetWindowLongPtr(_hwnd, GWL_STYLE); PInvokeWindows.SetWindowLongFlags dwNewStyle = (dwStyle & ~dwRemove) | dwAdd; if (dwStyle == dwNewStyle) { return(false); } PInvokeWindows.SetWindowLongPtr(_hwnd, GWL_STYLE, (IntPtr)dwNewStyle); return(true); }