【正文】 sicLength() As Long Dim RefStr As String * 80 mciSendString status NOWMUSIC length, RefStr, 80, 0 GetMusicLength = Val(RefStr) End Function 39。====================================================== 39。播放文件 39。======================================================= Public Function GetDriverID(ff As String) As String Select Case UCase(Right(ff, 3)) Case MID, RMI, IDI GetDriverID = Sequencer Case WAV GetDriverID = Waveaudio Case ASF, ASX, IVF, LSF, LSX, P2V, WAX, WVX, .WM, WMA, WMX, WMP GetDriverID = MPEGVideo2 Case .RM, RAM, .RA GetDriverID = RealPlayer Case Else GetDriverID = MPEGVideo End Select End Function 39。======================================================= 39。 style child 更多學(xué)習(xí)資源請(qǐng)登錄（ ） 上學(xué)吧為您提供 計(jì)算機(jī)二級(jí) VB 考試資料下載： hWndMusic = GetWindowHandle prevWndproc = GetWindowLong(hWndMusic, 4) SetWindowLong hWndMusic, 4, AddressOf WndProc Else MciCommand = MciCommand + style overlapped End If End If RefInt = mciSendString(MciCommand, vbNull, 0, 0) mciSendString set NOWMUSIC time format milliseconds, vbNullString, 0, 0 If RefInt = 0 Then OpenMusic = True End Function Function WndProc(ByVal hwnd As Long, ByVal Msg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long If Msg = amp。 alias NOWMUSIC If DriverID = AVIVideo Or DriverID = MPEGVideo Or DriverID = MPEGVideo2 Then If hwnd 0 Then MciCommand = MciCommand + parent amp。 type amp。MCI命令 DriverID = GetDriverID(RefShortName) If DriverID = RealPlayer Then PlayType = RealPlay Exit Function End If MciCommand = open amp。======================================================= Public Function OpenMusic(FileName As String, Optional hwnd As Long) As Boolean OpenMusic = False Dim ShortPathName As String * 255 Dim RefShortName As String Dim RefInt As Long Dim MciCommand As String Dim DriverID As String CloseMusic 39。======================================================= 39。 hwnd amp。 DriverID amp。 urlStr amp。======================================================= Public Function OpenURL(urlStr As String, Optional hwnd As Long) As Boolean OpenMusic = False Dim MciCommand As String Dim DriverID As String CloseMusic 39。======================================================= 39。left AudioRight = 2 39。 Public Declare Function mciSendString Lib Alias mciSendStringA (ByVal lpstrCommand As String, ByVal lpstrReturnString As String, ByVal uReturnLength As Long, ByVal hwndCallback As Long) As Long Public Declare Function mciGetDeviceID Lib Alias mciGetDeviceIDA 更多學(xué)習(xí)資源請(qǐng)登錄（ ） 上學(xué)吧為您提供 計(jì)算機(jī)二級(jí) VB 考試資料下載： (ByVal lpstrName As String) As Long Public Declare Function waveOutGetVolume Lib (ByVal uDeviceID As Long, lpdwVolume As Long) As Long Public Declare Function GetWindowLong Lib user32 Alias GetWindowLongA (ByVal hwnd As Long, ByVal nIndex As Long) As Long Public Declare Function CallWindowProc Lib user32 Alias CallWindowProcA (ByVal lpPrevWndFunc As Long, ByVal hwnd As Long, ByVal Msg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long Public Declare Function SetWindowLong Lib user32 Alias SetWindowLongA (ByVal hwnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long Public Declare Function GetShortPathName Lib kernel32 Alias GetShortPathNameA (ByVal lpszLongPath As String, ByVal lpszShortPath As String, ByVal cchBuffer As Long) As Long Enum PlayTypeName File = 1 CDAudio = 2 VCD = 3 RealPlay = 4 End Enum Dim PlayType As PlayTypeName Enum AudioSource AudioStereo = 0 39。用 MCI命令來實(shí)現(xiàn)多媒體的播放功能 39。H3 Public Const FOF_ALLOWUNDO = amp。 , vbInformation, 聲卡檢測(cè) End If 2如何找到 CDROM驅(qū)動(dòng)器的盤號(hào)？ 下 面的函數(shù)將檢查你計(jì)算機(jī)所有的驅(qū)動(dòng)器看是否是 CDROM，如果是就返回驅(qū)動(dòng)器號(hào)，如果沒有就返回空字符 Public Function GetCDROMDrive() As String Dim lType As Long,i As Integer,tmpDrive as String,found as Boolean On Error GoTo errL For i = 0 To 25 tmpDrive = Chr(65 + i) amp。H1 Declare Function SystemParametersInfo Lib user32 Alias SystemParametersInfoA (ByVal uAction As Long, ByVal uParam As Long, ByVal lpvParam As Any, ByVal fuWinIni As Long) As Long 注釋：調(diào)用 更多學(xué)習(xí)資源請(qǐng)登錄（ ） 上學(xué)吧為您提供 計(jì)算機(jī)二級(jí) VB 考試資料下載： Call SystemParametersInfo(SPI_SETDESKWALLPAPER, 0, C:, SPIF_UPDATEINIFILE) 2怎樣確定系統(tǒng)是否安裝了聲卡？ *API函數(shù)聲明： Declare Function waveOutGetNumDevs Lib Alias waveOutGetNumDevs () As Long 代碼如下： Dim i As Integer i = waveOutGetNumDevs() If i 0 Then MsgBox 你的系統(tǒng)可以播放聲音。 注釋：調(diào)用 Dim result As Long result = SendMessage(, WM_SYSCOMMAND, SC_SCREENSAVE, 0amp。 Const SC_SCREENSAVE = amp。 End Sub 1 VB中如何使用延時(shí)函數(shù)？ *API函數(shù)聲明： Declare Sub Sleep Lib kernel32 (ByVal dwMilliseconds As Long) 調(diào)用： 注釋：延時(shí) 1秒 Call Sleep(1000) 1調(diào)用修改屏幕保護(hù)口令的窗口： Private Declare Function PwdChangePassword Lib mpr Alias PwdChangePasswordA (ByVal lpcRegkeyname As String, ByVal hwnd As Long, ByVal uiReserved1 As Long, ByVal uiReserved2 As Long) As Long 調(diào)用： Call PwdChangePassword(SCRSAVE, , 0, 0) 1使 Windows開始屏幕保護(hù)： *API函數(shù)聲明 Private Declare Function SendMessage Lib user32 Alias SendMessageA (ByVal hWnd As Long, ByVal wMsg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long Const WM_SYSCOMMAND = amp。 1在程序中如何打開和關(guān)閉光驅(qū)門？ *API函數(shù)聲明如下 : Private Declare Function mciSendString Lib Alias mciSendStringA (ByVal lpstrCommand As String, ByVal lpstrReturnString As String, ByVal uReturnLength As Long, ByVal hwndCallback As Long) As Long 注釋：調(diào)用時(shí)的代碼如下 Dim Ret As Long Dim RetStr As String 注釋：打開光驅(qū)門 Ret = mciSendString(set CDAudio door open, RetStr, 0, 0) 注釋：關(guān)閉光驅(qū)門 更多學(xué)習(xí)資源請(qǐng)登錄（ ） 上學(xué)吧為您提供 計(jì)算機(jī)二級(jí) VB 考試資料下載： Ret = mciSendString(set