How MFC controls the size of music

DWORD cplaywave:: set volume (hwnd hwnd, dword value)

{

DWORD dw result = 0；

MCI _ DGV _ SETAUDIO _ PARMS mcisetadiopara；

mciset audio para . dw callback =(DWORD)hWnd；

MCI setaudiopara . dwitem = MCI _ DGV _ SETAUDIO _ VOLUME；

mciset audio para . dw Value = Value； //Volume value (0- 1000)

if(m_ElementID)

{

mciSendCommand(m_ElementID，MCI_SETAUDIO，MCI _ DGV _ SETAUDIO _ VALUE | MCI _ DGV _ SETAUDIO _ ITEM，(DWORD)(LPVOID)& amp； mciset audiopara)；

m _ element id = 0；

}

Return dwResult

}