C#代码实现单文件下载功能

 public static void DownFile(string URL, string Filename, ProgressBar Prog)
        {
            Prog.Visible = true;
            System.Net.HttpWebRequest Myrq = (System.Net.HttpWebRequest)System.Net.HttpWebRequest.Create(URL);
            System.Net.HttpWebResponse myrp = (System.Net.HttpWebResponse)Myrq.GetResponse();
            long totalBytes = myrp.ContentLength;
            Prog.Maximum = (int)totalBytes;
            System.IO.Stream st = myrp.GetResponseStream();
            System.IO.Stream so = new System.IO.FileStream(Filename, System.IO.FileMode.Create);
            long totalDownloadedByte = 0;
            byte[] by = new byte[1024];
            int osize = st.Read(by, 0, (int)by.Length);
            while (osize > 0)
            {
                totalDownloadedByte = osize + totalDownloadedByte;
                Application.DoEvents();
                so.Write(by, 0, osize);
                Prog.Value = (int)totalDownloadedByte;
                osize = st.Read(by, 0, (int)by.Length);
            }
            so.Close();
            st.Close();
            Prog.Visible = false;
        }

        private void button1_Click(object sender, EventArgs e)
        {
            DownFile("http://58.242.29.70:1983/QQkj/同桌的你.mp3", "D:\\同桌的你.mp3", progressBar1);
            DownFile("http://www.lbzzhy.com/images/zzhk.mp3", "D:\\xxhk.mp3", progressBar2);
            //DownFile("http://58.242.29.70:1983/QQkj/同桌的你.mp3", "D:\\同桌的你.mp3", progressBar3);