Option Strict Off
Option Explicit On
Imports VB = Microsoft.VisualBasic
Friend Class Form1
Inherits System.Windows.Forms.Form

Private Declare Function waveOutGetNumDevs Lib "winmm.dll" () As Integer
  
Private Declare Function waveOutSetVolume Lib "winmm.dll" (ByVal uDeviceID As Integer, ByVal dwVolume As Integer) As Integer
Private Declare Function waveOutGetVolume Lib "winmm.dll" (ByVal uDeviceID As Integer, ByRef lpdwVolume As Integer) As Integer

    Const Wave_mapper As Short = -1

    Public Function Setlr(ByVal Lvolume As Integer, ByVal Rvolume As Integer) As Integer
        Dim mlr As String
        mlr = "&h" & VB.Right("0000" & Hex(Lvolume), 4) & VB.Right("0000" & Hex(Rvolume), 4)
        waveOutSetVolume(Wave_mapper, CInt(mlr))
    End Function

    Public Function Getlr(ByRef l As Integer, ByRef r As Integer) As Integer
        Dim lr As Integer
        waveOutGetVolume(Wave_mapper, lr)
        l = CInt("&h" & VB.Left(Hex(lr), 4))
        r = CInt("&h" & VB.Right(Hex(lr), 4))
    End Function
Private Sub Form1_Load(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles MyBase.Load
Dim ml, mr As Integer
        Getlr(ml, mr)
        MsgBox("左声道" & ml & "--右声道" & mr)
End Sub

Private Sub command1_Click(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles command1.Click
Setlr(CInt(Text1.Text), CInt(Text2.Text))
End Sub
End Class