[boudyonline]

راجع هذا المثال واتمنى أن تستفيد منه :

كود :

Option Strict On

Imports System.Runtime.InteropServices

Public Class Form1

   Private Const APPCOMMAND_VOLUME_MUTE As Integer = &H80000
   Private Const APPCOMMAND_VOLUME_UP As Integer = &HA0000
   Private Const APPCOMMAND_VOLUME_DOWN As Integer = &H90000
   Private Const WM_APPCOMMAND As Integer = &H319

   <DllImport("user32.dll")> Public Shared Function SendMessageW(ByVal hWnd As IntPtr, ByVal Msg As Integer, ByVal wParam As IntPtr, ByVal lParam As IntPtr) As IntPtr
   End Function

   Dim HScroll3 As Integer = 0
   Dim Count As Integer = 0

   Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
       SendMessageW(Me.Handle, WM_APPCOMMAND, Me.Handle, New IntPtr(APPCOMMAND_VOLUME_MUTE))
   End Sub


   Private Sub HScrollBar3_Scroll(sender As Object, e As ScrollEventArgs) Handles HScrollBar3.Scroll
       If Count = 1 Then
           If HScrollBar3.Value > HScroll3 Then
               SendMessageW(Me.Handle, WM_APPCOMMAND, Me.Handle, New IntPtr(APPCOMMAND_VOLUME_UP))
           End If
           If HScrollBar3.Value < HScroll3 Then
               SendMessageW(Me.Handle, WM_APPCOMMAND, Me.Handle, New IntPtr(APPCOMMAND_VOLUME_DOWN))
           End If
       End If
       HScroll3 = HScrollBar3.Value
       Count = 1
   End Sub
End Class