function ForceForegroundWindow(hwnd: THandle): Boolean; const SPI_GETFOREGROUNDLOCKTIMEOUT = $2000; SPI_SETFOREGROUNDLOCKTIMEOUT = $2001; var ForegroundThreadID: DWORD; ThisThreadID: DWORD; timeout: DWORD; begin if IsIconic(hwnd) then ShowWindow(hwnd, SW_RESTORE); if GetForegroundWindow = hwnd then Result := True else begin // Windows 98/2000 doesn't want to foreground a window when some other // window has keyboard focus if ((Win32Platform = VER_PLATFORM_WIN32_NT) and (Win32MajorVersion > 4)) or ((Win32Platform = VER_PLATFORM_WIN32_WINDOWS) and ((Win32MajorVersion > 4) or ((Win32MajorVersion = 4) and (Win32MinorVersion > 0)))) then begin // Code from Karl E. Peterson, www.mvps.org/vb/sample.htm // Converted to Delphi by Ray Lischner // Published in The Delphi Magazine 55, page 16 Result := False; ForegroundThreadID := GetWindowThreadProcessID(GetForegroundWindow, nil); ThisThreadID := GetWindowThreadPRocessId(hwnd, nil); if AttachThreadInput(ThisThreadID, ForegroundThreadID, True) then begin BringWindowToTop(hwnd); // IE 5.5 related hack SetForegroundWindow(hwnd); AttachThreadInput(ThisThreadID, ForegroundThreadID, False); Result := (GetForegroundWindow = hwnd); end; if not Result then begin // Code by Daniel P. Stasinski SystemParametersInfo(SPI_GETFOREGROUNDLOCKTIMEOUT, 0, @timeout, 0); SystemParametersInfo(SPI_SETFOREGROUNDLOCKTIMEOUT, 0, TObject(0), SPIF_SENDCHANGE); BringWindowToTop(hwnd); // IE 5.5 related hack SetForegroundWindow(hWnd); SystemParametersInfo(SPI_SETFOREGROUNDLOCKTIMEOUT, 0, TObject(timeout), SPIF_SENDCHANGE); end; end else begin BringWindowToTop(hwnd); // IE 5.5 related hack SetForegroundWindow(hwnd); end; Result := (GetForegroundWindow = hwnd); end; end; { ForceForegroundWindow } // 2. Way: //**********************************************procedure ForceForegroundWindow(hwnd: THandle); // (W) 2001 Daniel Rolf // http://www.finecode.de // [email protected] var hlp: TForm; begin hlp := TForm.Create(nil); try hlp.BorderStyle := bsNone; hlp.SetBounds(0, 0, 1, 1); hlp.FormStyle := fsStayOnTop; hlp.Show; mouse_event(MOUSEEVENTF_ABSOLUTE or MOUSEEVENTF_LEFTDOWN, 0, 0, 0, 0); mouse_event(MOUSEEVENTF_ABSOLUTE or MOUSEEVENTF_LEFTUP, 0, 0, 0, 0); SetForegroundWindow(hwnd); finally hlp.Free; end; end;// 3. Way: //********************************************** // by Thomas Stutz{ As far as you know the SetForegroundWindow function on Windows 98/2000 can not force a window to the foreground while the user is working with another window. Instead, SetForegroundWindow will activate the window and call the FlashWindowEx function to notify the user. However in some kind of applications it is necessary to make another window active and put the thread that created this window into the foreground and of course, you can do it using one more undocumented function from the USER32.DLL. void SwitchToThisWindow (HWND hWnd, // Handle to the window that should be activated BOOL bRestore // Restore the window if it is minimized );}procedure SwitchToThisWindow(h1: hWnd; x: bool); stdcall; external user32 Name 'SwitchToThisWindow'; {x = false: Size unchanged, x = true: normal size} procedure TForm1.Button2Click(Sender: TObject); begin SwitchToThisWindow(FindWindow('notepad', nil), True); end;
然后,找出 A1,A2 程序的Handle(根据窗口名)
与自己 Application.MainForm.Handle 不同的,就是另外一个程序了,然后,用下面的代码切换过去
const
SPI_GETFOREGROUNDLOCKTIMEOUT = $2000;
SPI_SETFOREGROUNDLOCKTIMEOUT = $2001;
var
ForegroundThreadID: DWORD;
ThisThreadID: DWORD;
timeout: DWORD;
begin
if IsIconic(hwnd) then ShowWindow(hwnd, SW_RESTORE); if GetForegroundWindow = hwnd then Result := True
else
begin
// Windows 98/2000 doesn't want to foreground a window when some other
// window has keyboard focus if ((Win32Platform = VER_PLATFORM_WIN32_NT) and (Win32MajorVersion > 4)) or
((Win32Platform = VER_PLATFORM_WIN32_WINDOWS) and
((Win32MajorVersion > 4) or ((Win32MajorVersion = 4) and
(Win32MinorVersion > 0)))) then
begin
// Code from Karl E. Peterson, www.mvps.org/vb/sample.htm
// Converted to Delphi by Ray Lischner
// Published in The Delphi Magazine 55, page 16 Result := False;
ForegroundThreadID := GetWindowThreadProcessID(GetForegroundWindow, nil);
ThisThreadID := GetWindowThreadPRocessId(hwnd, nil);
if AttachThreadInput(ThisThreadID, ForegroundThreadID, True) then
begin
BringWindowToTop(hwnd); // IE 5.5 related hack
SetForegroundWindow(hwnd);
AttachThreadInput(ThisThreadID, ForegroundThreadID, False);
Result := (GetForegroundWindow = hwnd);
end;
if not Result then
begin
// Code by Daniel P. Stasinski
SystemParametersInfo(SPI_GETFOREGROUNDLOCKTIMEOUT, 0, @timeout, 0);
SystemParametersInfo(SPI_SETFOREGROUNDLOCKTIMEOUT, 0, TObject(0),
SPIF_SENDCHANGE);
BringWindowToTop(hwnd); // IE 5.5 related hack
SetForegroundWindow(hWnd);
SystemParametersInfo(SPI_SETFOREGROUNDLOCKTIMEOUT, 0, TObject(timeout), SPIF_SENDCHANGE);
end;
end
else
begin
BringWindowToTop(hwnd); // IE 5.5 related hack
SetForegroundWindow(hwnd);
end; Result := (GetForegroundWindow = hwnd);
end;
end; { ForceForegroundWindow }
// 2. Way:
//**********************************************procedure ForceForegroundWindow(hwnd: THandle);
// (W) 2001 Daniel Rolf
// http://www.finecode.de
// [email protected]
var
hlp: TForm;
begin
hlp := TForm.Create(nil);
try
hlp.BorderStyle := bsNone;
hlp.SetBounds(0, 0, 1, 1);
hlp.FormStyle := fsStayOnTop;
hlp.Show;
mouse_event(MOUSEEVENTF_ABSOLUTE or MOUSEEVENTF_LEFTDOWN, 0, 0, 0, 0);
mouse_event(MOUSEEVENTF_ABSOLUTE or MOUSEEVENTF_LEFTUP, 0, 0, 0, 0);
SetForegroundWindow(hwnd);
finally
hlp.Free;
end;
end;// 3. Way:
//**********************************************
// by Thomas Stutz{
As far as you know the SetForegroundWindow function on Windows 98/2000 can
not force a window to the foreground while the user is working with another window.
Instead, SetForegroundWindow will activate the window and call the FlashWindowEx
function to notify the user. However in some kind of applications it is necessary
to make another window active and put the thread that created this window into the
foreground and of course, you can do it using one more undocumented function from
the USER32.DLL. void SwitchToThisWindow (HWND hWnd, // Handle to the window that should be activated
BOOL bRestore // Restore the window if it is minimized
);}procedure SwitchToThisWindow(h1: hWnd; x: bool); stdcall;
external user32 Name 'SwitchToThisWindow';
{x = false: Size unchanged, x = true: normal size}
procedure TForm1.Button2Click(Sender: TObject);
begin
SwitchToThisWindow(FindWindow('notepad', nil), True);
end;