原文：http://www.vckbase.com/index.php/wv/94
服务程序（Service）一般是不能和用户进行交互的，所以他一般是不能显示窗口的。要和用户进行交互（如显示窗口），我们必须打开用户WinSta0和desktop,下面的这段代码就是打开上述两个，并显示一个dialog：
01.BOOL CServiceModule::ShowMsgDlg(void)
02.{
03.HDESK hdeskCurrent;
04.HDESK hdesk;
05.HWINSTA hwinstaCurrent;
06.HWINSTA hwinsta;
07. 08.hwinstaCurrent
= GetProcessWindowStation();
09.if (hwinstaCurrent
== NULL){
10.LogEvent(_T("get
window station err"));
11.return FALSE;
12.}
13. 14.hdeskCurrent
= GetThreadDesktop(GetCurrentThreadId());
15.if (hdeskCurrent
== NULL){
16.LogEvent(_T("get
window desktop err"));
17.return FALSE;
18.}
19. 20.//打开winsta0
21.hwinsta
= OpenWindowStation("winsta0",
FALSE,
22.WINSTA_ACCESSCLIPBOARD
|
23.WINSTA_ACCESSGLOBALATOMS
|
24.WINSTA_CREATEDESKTOP
|
25.WINSTA_ENUMDESKTOPS
|
26.WINSTA_ENUMERATE
|
27.WINSTA_EXITWINDOWS
|
28.WINSTA_READATTRIBUTES
|
29.WINSTA_READSCREEN
|
30.WINSTA_WRITEATTRIBUTES);
31.if (hwinsta
== NULL){
32.LogEvent(_T("open
window station err"));
33. 34.return FALSE;
35.}
36. 37.if (!SetProcessWindowStation(hwinsta)){
38.LogEvent(_T("Set
window station err"));
39. 40.return FALSE;
41.}
42. 43.//打开desktop
44.hdesk
= OpenDesktop("default",
0, FALSE,
45.DESKTOP_CREATEMENU
|
46.DESKTOP_CREATEWINDOW
|
47.DESKTOP_ENUMERATE
|
48.DESKTOP_HOOKCONTROL
|
49.DESKTOP_JOURNALPLAYBACK
|
50.DESKTOP_JOURNALRECORD
|
51.DESKTOP_READOBJECTS
|
52.DESKTOP_SWITCHDESKTOP
|
53.DESKTOP_WRITEOBJECTS);
54.if (hdesk
== NULL){
55.LogEvent(_T("Open
desktop err"));
56. 57.return FALSE;
58.}
59. 60.SetThreadDesktop(hdesk);
61. 62.//到这一步，我们获取了和用户交互（如显示窗口）的权利
63.CMsgDlg
dlgMsg;
64.//显示一个dialog
65.dlgMsg.DoModal();
66. 67.if (!SetProcessWindowStation(hwinstaCurrent))
68.return FALSE;
69. 70.if (!SetThreadDesktop(hdeskCurrent))
71.return FALSE;
72. 73.if (!CloseWindowStation(hwinsta))
74.return FALSE;
75. 76.if (!CloseDesktop(hdesk))
77.return FALSE;
78. 79.return TRUE;
80.}