VB初学者实例50例

End Sub 
Function PlaySound(ByVal FileName As String) As Boolean 
 Dim cmd As String, exName As String 
 exName = Right(FileName, 3) 
 mciSendString "close " & exName, 0, 0, 0 
 cmd = "open " & FileName & " alias " & exName 
 mciSendString cmd, 0, 0, 0 
 PlaySound = mciSendString("play " & exName, 0, 0, 0) 
End Function 
Private Sub Command2_Click() 
 Static flag As Boolean ' 设置左声道开关 
 mciSendString "set all audio all " & IIf(flag, "on", "off"), 0, 0, 0 
 If flag = False Then 
 Command2.Caption = "左声道(关)" 
 Else 
 Command2.Caption = "左声道(开)" 
 End If 
 flag = Not flag 
End Sub 
Private Sub Command3_Click() 
 Static flag As Boolean ' 设置右声道开关 
 mciSendString "set all audio all " & IIf(flag, "on", "off"), 0, 0, 0 
 If flag = False Then 
 Command3.Caption = "右声道(关)" 
 Else 
 Command3.Caption = "右声道(开)" 
 End If 
 flag = Not flag 
End Sub 
Private Sub Command4_Click() '' 设置mp3设备音量:0--1000,500表示音量适中 
 mciSendString "set mp3 audio volume to 500", 0, 0, 0  
End Sub