C#调节音量

SendMessage(this.Handle, WM_APPCOMMAND, 0x30292, APPCOMMAND_VOLUME_UP * 0x10000); //音量加
SendMessage(this.Handle, WM_APPCOMMAND, 0x30292, APPCOMMAND_VOLUME_DOWN * 0x10000);//音量减
  SendMessage(this.Handle, WM_APPCOMMAND, 0x200eb0, APPCOMMAND_VOLUME_MUTE * 0x10000); //静音
        [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;