如何写下载器（急）

Question

如何写下载器（急）

Answer 1

单线程下载
        /// <summary>
        /// 下载文件
        /// </summary>
        private void StartDownLoad()
        {
            string url = string.Empty;
            string fileName = string.Empty;
            int n = 0;
            string path = string.Empty;
            url = txtURI.Text;
            n = url.LastIndexOf('/');
            fileName = url.Substring(n + 1);
            path = txtbLocal.Text + "\\" + fileName;
                try
                {
                    WebRequest request = WebRequest.Create(url);
                }
                catch (WebException ex)
                {
                    MessageBox.Show(ex.Message, "Error");
                }                try
                {
                    WebClient client = new WebClient();
                    stBar.Text = "开始下载文件...";
                    client.DownloadFile(url, path);
                    stBar.Text = "下载完毕,文件已经保存到" + path.ToString();
                }
                catch (WebException ex)
                {
                    MessageBox.Show(ex.Message, "Error");
                    stBar.Text = string.Empty;
                }
                finally
                {
                    btnDownLoad.Enabled = true;
                }
        }        private void btnDownLoad_Click_1(object sender, EventArgs e)
        {
           //开启线程,以改善用户体验.
           Thread th=new Thread(new ThreadStart(StartDownLoad));
           //th.Name="New DownLoad";
           th.Start();
        }

Answer 2

多线程：
http://www.51aspx.com/CV/MultiThreadDownLoadFile/