[摘要]MCI_WAIT, (DWORD)(LPVOID)&mciOpenParms); //save device identifier,will use eith other MCI comma... MCI_WAIT, (DWORD)(LPVOID)&mciOpenParms); //save device identifier,will use eith other MCI commands
m_nDeviceID=mciOpenParms.wDeviceID; //display error message if failed if(dwResult)
DisplayErrorMsg(dwResult);
} //return result of MCI operation return dwResult; }
DWORD CWave::CloseDevice()
{
DWORD dwResult=0; //close if currently open if(m_nDeviceID) { //close the MCI device
dwResult=mciSendCommand(m_nDeviceID,MCI_CLOSE,NULL,NULL); //display error message if failed
if(dwResult) DisplayErrorMsg(dwResult); //set identifier to close state else m_nDeviceID=0; } //return result of MCI operation return dwResult;
}
DWORD CWave::Play(CWnd* pWnd,LPCSTR pFileName)
{
MCI_OPEN_PARMS mciOpenParms; //initialize structure
memset(&mciOpenParms,0,sizeof(MCI_OPEN_PARMS)); //set the WAV file name to be played
mciOpenParms.lpstrElementName=pFileName; //first open the device DWORD
dwResult=mciSendCommand(m_nDeviceID,MCI_OPEN, MCI_OPEN_ELEMENT,(DWORD)(LPVOID)&mciOpenParms); //display error message if failed if(dwResult)
DisplayErrorMsg(dwResult); //if successful,instruct the device to play the WAV file else { //save element indentifier m_nElementID=mciOpenParms.wDeviceID; MCI_PLAY_PARMS mciPlayParms; //set the window that will receive notification message
mciPlayParms.dwCallback=(DWORD)pWnd->m_hWnd; //instruct device to play file
dwResult=mciSendCommand(m_nElementID,MCI_PLAY, MCI_NOTIFY,(DWORD)(LPVOID)&mciPlayParms); //display error and close element if failed if(dwResult) { DisplayErrorMsg(dwResult); Stop(); }
} //return result of MCI operation return dwResult; }
DWORD CWave::Stop()
{
DWORD dwResult=0; //close if element is currently open if(m_nElementID) {
dwResult=mciSendCommand(m_nElementID,MCI_CLOSE,NULL,NULL); //display error message if failed
if(dwResult) DisplayErrorMsg(dwResult); //set identifier to closed state else
m_nElementID=0;
return dwResult;
}
void CWave::DisplayErrorMsg(DWORD dwError)
{ //check if there was an error
if(dwError)
{ //character string that contains error message
char szErrorMsg［MAXERRORLENGTH］; //retrieve string associated error message
if(!mciGetErrorString(dwError,szErrorMsg,sizeof(szErrorMsg))) strcpy(szErrorMsg,"Unknown Error"); //display error string in message box
AfxMessageBox(szErrorMsg);
}
} |