怎么在VB界面加背景音乐

Private Declare Function mciSendString Lib "winmm.dll" Alias "mciSendStringA" (ByVal lpstrCommand As String, ByVal lpstrReturnString As String, ByVal uReturnLength As Long, ByVal hwndCallback As Long) As Long

Private Sub Form_Load()
mciSendString "open C:\birthday.mid alias mc", 0, 0, 0
mciSendString "play mc", 0, 0, 0
End Sub

Public Const SND_NOWAIT = &&H2000

Public Const SND_VALIDFLAGS = &&H17201F

Public Const SND_RESERVED = &&HFF000000

Public Const SND_TYPE_MASK = &&H170007

Private Declare Function sndPlaySound Lib "winmm.dll" Alias "sndPlaySoundA" (ByVal lpszSoundName As String, ByVal uFlags As Long) As Long

sndPlaySound函数需要两个参数：第一个参数soundfilename是要播放的WAV文件的名称；第二个参数是一个表明播放方式的标识常量，其定义的值如前面的声明所示，通常所使用的标识意义如下：

SND_SYNC播放WAV格式文件，播放完毕后将控制转移回应用中。

SND_ASYNC播放WAV格式文件，将控制立即转移回应用程序中，而不管对WAV文件的播放是否