Windows Forms – FlashWindowEx implementation

A nice way to alert your users when your Windows Forms application is not active, and a certain task is complete.

public enum FLASHWINFOFLAGS
{
  FLASHW_STOP = 0,
  FLASHW_CAPTION = 0x00000001,
  FLASHW_TRAY = 0x00000002,
  FLASHW_ALL = (FLASHW_CAPTION | FLASHW_TRAY),
  FLASHW_TIMER = 0x00000004,
  FLASHW_TIMERNOFG = 0x0000000C
}

[StructLayout(LayoutKind.Sequential)]
public struct FLASHWINFO
{
  public UInt32 cbSize;
  public IntPtr hwnd;
  public Int32 dwFlags;
  public UInt32 uCount;
  public Int32 dwTimeout;
}

[DllImport("user32.dll")]
public static extern int FlashWindowEx(ref FLASHWINFO pfwi);

// Example use
private void dBrowser_DocumentCompleted(
  object sender,
  WebBrowserDocumentCompletedEventArgs e)
{
  if (!IsActive)
  {
    // Flash the window
    FLASHWINFO fwi = new FLASHWINFO();
    fwi.cbSize = Convert.ToUInt32(Marshal.SizeOf(typeof(FLASHWINFO)));
    fwi.hwnd = this.Handle;
    fwi.dwFlags = (Int32)
      (FLASHWINFOFLAGS.FLASHW_ALL | FLASHWINFOFLAGS.FLASHW_TIMERNOFG);
    fwi.dwTimeout = 0;

    FlashWindowEx(ref fwi);
  }
}