逆风编程精品
　　1、找到windows和system目录的安装位置

　　2、把屏幕保护文件复制到system目录下

　　3、在system.ini中的[boot]中写入:

　　　　SCRNSAVE.EXE=C:\WINDOWS\SYSTEM\工程1.SCR

　　4、告诉系统切换屏幕保护。

　　下面的例子成功地改变了屏幕保护，全部源代码如下：

'得到windows目录

Private Declare Function GetWindowsDirectory Lib "kernel32" Alias "GetWindowsDirectoryA" (ByVal lpBuffer As String, ByVal nSize As Long) As Long

'修改system.ini
Private Declare Function WritePrivateProfileString Lib "kernel32" Alias "WritePrivateProfileStringA" (ByVal lpApplicationName As String, ByVal lpKeyName As Any, ByVal lpString As Any, ByVal lplFileName As String) As Long

'得到system目录
Private Declare Function GetSystemDirectory Lib "kernel32" Alias "GetSystemDirectoryA" (ByVal lpBuffer As String, ByVal nSize As Long) As Long

'设置屏幕保护
Private Const SPI_SETSCREENSAVETIMEOUT = 15
Private Const SPI_SETSCREENSAVEACTIVE = 17
Private Const SPIF_UPDATEINIFILE = &H1
Private Const SPIF_SENDWININICHANGE = &H2

Private Declare Function SystemParametersInfo Lib "user32" Alias "SystemParametersInfoA" (ByVal uAction As Long, ByVal uParam As Long, ByVal lpvParam As Long, ByVal fuWinIni As Long) As Long

'启动屏幕保护
Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam As Any) As Long

Private Const WM_SYSCOMMAND = &H112
Private Const SC_SCREENSAVE = &HF140

Private Sub Form_Load()
　 '得到system目录
　 Dim sSave As String, Ret As Long
　 sSave = Space(255)
　 Ret = GetSystemDirectory(sSave, 255)
　 sSave = Left$(sSave, Ret)
　 '把屏保复制到系统目录
　 FileCopy App.Path & "\工程1.scr", sSave & "\工程1.SCR"
　 '得到windows目录
　 Dim Path As String, strSave As String
　 strSave = String(250, Chr$(0))
　 Path = Left$(strSave, GetWindowsDirectory(strSave, Len(strSave)))
　 '修改system.ini
　 Dim r As Long
　 Dim iniPath As String
　 iniPath$ = Path "\system.ini"
　 r = WritePrivateProfileString("boot", "SCRNSAVE.EXE", sSave & "\工程1.SCR", iniPath)
　 '设置时间间隔为1分钟=60秒
　 lRet = SystemParametersInfo(SPI_SETSCREENSAVETIMEOUT, 60, ByVal 0&, 　
　　　　 SPIF_UPDATEINIFILE SPIF_SENDWININICHANGE)
　 '设置屏幕保护
　 retval = SystemParametersInfo(SPI_SETSCREENSAVEACTIVE, True, 0, 0)
　 '启动屏幕保护
　 Dim result As Long
result = SendMessage(Form1.hwnd, WM_SYSCOMMAND, SC_SCREENSAVE, 0&)
End Sub