/// <summary>
/// This variant of IsWindowActivated simply checks whether a specified window handle
/// is currently focused rather than whether any window belonging to the current process
/// is focused.
/// </summary>
/// <returns>Returns true if the specified handle has focus, else false.</returns>
public static bool IsWindowActivated(IntPtr windowHandle)
{
// Obtain the active window handle.
IntPtr activatedHandle = WindowFunctions.GetForegroundWindow();
// Check if any window is active.
if (activatedHandle == IntPtr.Zero)
{
return(false);
}
// Compare the process identifiers of active window and our process.
return(activatedHandle == windowHandle);
}
/// <summary>
/// Checks whether the current application is activated.
/// The method compares the current active foreground window to the
/// window thread of the current caller.
///
/// The function is not specific
/// to any technology and works for both child windows and the current window,
/// also independently of the thread which owns a specific window.
/// </summary>
/// <returns>Returns true if the current application has focus/is foreground/is activated. Else false.</returns>
public static bool IsWindowActivated()
{
// Obtain the active window handle.
IntPtr activatedHandle = WindowFunctions.GetForegroundWindow();
// Check if any window is active.
if (activatedHandle == IntPtr.Zero)
{
return(false);
}
// Retrieve unique identifier for this process.
int currentProcessIdentifier = System.Diagnostics.Process.GetCurrentProcess().Id;
// Retrieve the process identifier for the active window.
WindowFunctions.GetWindowThreadProcessId(activatedHandle, out int activeProcessIdentifier);
// Compare the process identifiers of active window and our process.
return(activeProcessIdentifier == currentProcessIdentifier);
}