公司禁用用迅雷，禁用所有P2P协议的软件，自己写个断点续传的工具

public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();            
        }
        private void DownLoad()
        {
            XmlDocument xmlDoc = new XmlDocument();
            xmlDoc.Load("D:\\中转\\data.xml");
            XmlNodeList nodeList = xmlDoc.SelectSingleNode("data").ChildNodes;
            XmlElement xe = (XmlElement)nodeList.Item(nodeList.Count - 1);
            if (xe.GetAttribute("is_finish").Equals("true"))
            {
                MessageBox.Show("none task in the list");
                return;
            }
            string StrFileName = "D:\\中转\\" + xe.GetAttribute("name"); 
            string StrUrl = xe.GetAttribute("address");
            long lStartPos = 0;
            System.IO.FileStream fs;
            if (System.IO.File.Exists(StrFileName))
            {
                fs = System.IO.File.OpenWrite(StrFileName);
                lStartPos = fs.Length;
                fs.Seek(lStartPos, System.IO.SeekOrigin.Current); //移动文件流中的当前指针
            }
            else
            {
                fs = new System.IO.FileStream(StrFileName, System.IO.FileMode.Create);
                lStartPos = 0;
            }
            //打开网络连接
            try
            {
                System.Net.HttpWebRequest request = (System.Net.HttpWebRequest)System.Net.HttpWebRequest.Create(StrUrl);
                if (lStartPos > 0)
                    request.AddRange((int)lStartPos); //设置Range值
                //向服务器请求，获得服务器回应数据流
                System.IO.Stream ns = request.GetResponse().GetResponseStream();
                byte[] nbytes = new byte[512];
                int nReadSize = 0;
                nReadSize = ns.Read(nbytes, 0, 512);                
                while (nReadSize > 0)
                {
                    fs.Write(nbytes, 0, nReadSize);
                    nReadSize = ns.Read(nbytes, 0, 512);
                }
                fs.Close();
                ns.Close();
                EditNode();
                MessageBox.Show("Down Ok!");
            }
            catch (Exception ex)
            {
                fs.Close();
                MessageBox.Show("Down Error!");
            }
        }
        private void notifyIcon1_MouseClick(object sender, MouseEventArgs e)
        {
            XmlDocument xmlDoc = new XmlDocument();
            xmlDoc.Load("D:\\中转\\data.xml");
            XmlNodeList nodeList = xmlDoc.SelectSingleNode("data").ChildNodes;
            XmlElement xe = (XmlElement)nodeList.Item(nodeList.Count - 1);
            string StrFileName = "D:\\中转\\" + xe.GetAttribute("name");
            FileInfo fi = new FileInfo(StrFileName);
            DialogResult dr = MessageBox.Show(this, string.Format("already:{0}kb\nOK:exit\ncancel:continue", fi.Length / 1024), "提示", MessageBoxButtons.OKCancel, MessageBoxIcon.Question,MessageBoxDefaultButton.Button2);
            if (!dr.Equals(DialogResult.Cancel))
            {
                this.Close();
                this.Dispose();
            }
        }
        private void button1_Click(object sender, EventArgs e)
        {
            this.Hide();
            if (!string.IsNullOrEmpty(textBox1.Text.Trim())&&!string.IsNullOrEmpty(textBox2.Text.Trim()))
            {
                InsertNode();
            }
            System.Threading.Thread obj = new System.Threading.Thread(new System.Threading.ThreadStart(this.DownLoad));
            //设置为前台线程，即使主方法执行结束了我的线程仍在执行
            obj.IsBackground = true;
            obj.Start();
        }
        private void EditNode()
        {
            XmlDocument xmlDoc = new XmlDocument();
            xmlDoc.Load("D:\\中转\\data.xml");
            XmlNodeList nodeList = xmlDoc.SelectSingleNode("data").ChildNodes;
            XmlElement xe = (XmlElement)nodeList.Item(nodeList.Count - 1);
            xe.SetAttribute("is_finish", "true");
            xmlDoc.Save("D:\\中转\\data.xml");//保存。
        }
        private void InsertNode()
        {
            XmlDocument xmlDoc = new XmlDocument();
            xmlDoc.Load("D:\\中转\\data.xml");
            XmlNode root = xmlDoc.SelectSingleNode("data");
            XmlElement xe1 = xmlDoc.CreateElement("file");
            xe1.SetAttribute("name", textBox1.Text.Trim());
            xe1.SetAttribute("address", textBox2.Text.Trim());
            xe1.SetAttribute("is_finish", "false");
            root.AppendChild(xe1);
            xmlDoc.Save("D:\\中转\\data.xml");
        }