static extern bool AllowSetForegroundWindow(int dwProcessId);

Shared Function AllowSetForegroundWindow(ByVal dwProcessId As Integer) As Boolean

AllowSetForegroundWindow(System.Diagnostics.Process.GetCurrentProcess().Id)

- The foreground is not locked (see LockSetForegroundWindow).

        public static extern int SetForegroundWindow( IntPtr Hwnd );

                SetForegroundWindow( Hwnd );

      private static extern bool SetForegroundWindow(IntPtr hWnd);

          SetForegroundWindow(hWnd);

Use FindWindow and SetForegroundWindow to direct input to the desired window.

  SetForegroundWindow (FindWindow('Untitled - Notepad'))

static extern bool LockSetForegroundWindow(uint uLockCode);

Public Shared Function LockSetForegroundWindow(uLockCode As UInteger) As <MarshalAs(UnmanagedType.Bool)> Boolean

   Api.user32.SetForegroundWindow(hWindow);

   [testing.windows]::SetForegroundWindow( @( Get-Process notepad |? { $_.id -in @( get-wmiobject win32_process -filter "name='notepad.exe'" |% { if ( $_.getowner().user -eq $env:username ) { $_.processid } } ) } )[0].MainWindowHandle)

- The SetForegroundWindow API

    ///     <item>The foreground is not locked (see LockSetForegroundWindow).</item>

    ///     calling the AllowSetForegroundWindow function. The process specified by dwProcessId loses the ability to set

    ///     the next time a process calls AllowSetForegroundWindow, unless that process is specified.

    ///     The foreground process can disable calls to SetForegroundWindow by calling the LockSetForegroundWindow

static extern bool SetForegroundWindow(IntPtr hWnd);

Private Shared Function SetForegroundWindow(ByVal hWnd As IntPtr) As <MarshalAs(UnmanagedType.Bool)> Boolean

Private Declare Function SetForegroundWindow Lib "user32" (ByVal hwnd As IntPtr) As Long

SetForegroundWindow Win32-API not always works on Windows-7 (vista and above).

http://www.shloemi.com/2012/09/solved-setforegroundwindow-win32-api-not-always-works/

        SetForegroundWindow(hWnd);

                return SetForegroundWindow((IntPtr)hWnd);

http://jorgearimany.blogspot.com/2010/10/win32-setforegroundwindow-equivalent-in.html

- [SetForegroundWindow] on MSDN

    ///     SetForegroundWindow function.

    ///     SetForegroundWindow permission.

private static extern bool SetForegroundWindow(IntPtr hWnd);

    SetForegroundWindow (GetDesktopWindow());

If you are searching for a way to send keys to an application, you can use System.Windows.Forms.SendKeys.Send(keys) after bringing the window to the top via the SetForegroundWindow API.

private static extern bool SetForegroundWindow (IntPtr hWnd);

Private Shared Function SetForegroundWindow(ByVal hWnd As IntPtr) As Boolean

Private Declare Function SetForegroundWindow Lib "coredll" (hWnd as IntPtr) As Boolean

http://www.pinvoke.net/default.aspx/user32/SetForegroundWindow.html

E.g. SetForegroundWindow((HWND)(((ULONG) hwnd) | 0x01) );

private static extern bool SetForegroundWindow (IntPtr hWnd);

    SetForegroundWindow (GetDesktopWindow ());

         NativeWindow.SetForegroundWindow(this.Handle);

static extern void CoAllowSetForegroundWindow(

    /// To activate the window, use the SetActiveWindow or SetForegroundWindow function.

    ''' To activate the window, use the SetActiveWindow or SetForegroundWindow function.

    /// To activate the window, use the SetActiveWindow or SetForegroundWindow function.

    ''' To activate the window, use the SetActiveWindow or SetForegroundWindow function.