请教“怎样用VB做一个计时器倒计时，计时完了放一首MP3格式的歌”谢谢

添加一个Timer控件

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

Const SND_SYNC = &H0 '播放声音的同时，不允许运行其它程序
Const SND_ASYNC = &H1 '播放声音的同时，允许运行其它程序
Const SND_NODEFAULT = &H2
Const SND_MEMORY = &H4
'Const SND_LOOP = &H8
Const SND_NOSTOP = &H10
Dim strtemp

Private Sub PlaySound(strSound As String)
sndPlaySound strSound, SND_SYNC
End Sub

Private Sub Form_Load()
Timer1.Interval = 1000
Timer1.enabled= true
End Sub

Private Sub Timer1_Timer()
sndPlaySound "G:\启动.wav", SND_ASYNC
End Sub

//在Timer()中添加DateDiff()来计算剩余时间