Windowsボリュームの制御

public partial class AdjustVolume

    {

        [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]

        static extern IntPtr SendMessage(IntPtr hWnd, uint Msg, uint wParam, uint lParam);



        const uint WM_APPCOMMAND = 0x319;

        const uint APPCOMMAND_VOLUME_UP = 0x0a;

        const uint APPCOMMAND_VOLUME_DOWN = 0x09;

        const uint APPCOMMAND_VOLUME_MUTE = 0x08;





      public  static void PlusVolume(IntPtr hWnd)

        {

            // 

            SendMessage(hWnd, WM_APPCOMMAND, 0x30292, APPCOMMAND_VOLUME_UP * 0x10000);

        }

      public static void MinusVolume(IntPtr hWnd)

        {

            // 

            SendMessage(hWnd, WM_APPCOMMAND, 0x30292, APPCOMMAND_VOLUME_DOWN * 0x10000);

        }

      public static void MuteSwitch(IntPtr hWnd)

        {

            // 

            SendMessage(hWnd, WM_APPCOMMAND, 0x200eb0, APPCOMMAND_VOLUME_MUTE * 0x10000);

        }

    }