Question

我想用c#中的trackbar控件来实现音量的控制，应该怎么写代码？在线等大神。谢谢

Answer 1

    public partial class Form1 : Form
    {
        [DllImport("winmm.dll")]
        internal static extern int waveOutGetVolume(IntPtr hwo, out uint dwVolume);
        [DllImport("winmm.dll")]
        internal static extern int waveOutSetVolume(IntPtr hwo, uint dwVolume);
        public Form1()
        {
            InitializeComponent();
        }

        private void trackBar1_Scroll(object sender, EventArgs e)
        {
            uint currV = ushort.MaxValue / 2;
            waveOutGetVolume(IntPtr.Zero, out currV);
            ushort calcV = (ushort)(currV & 0x0000ffff);
            int newV = ((ushort.MaxValue / 100) * trackBar1.Value);
            uint newVol = (((uint)newV & 0x0000ffff) | ((uint)newV << 16));
            waveOutSetVolume(IntPtr.Zero, newVol);
            //下面这句是为了显示调整百分比
            Text = Convert.ToString("Volume: " + trackBar1.Value + "%");
        }
    }