C#实现远程下载Winrar压缩包

代码：

using System;

using System.Data;

using System.Configuration;

using System.Web;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Web.UI.HtmlControls;

using System.Text;

using System.IO;

public partial class _Default : System.Web.UI.Page

{

protected void Page_Load(object sender, EventArgs e)

{

DownloadClass dd = new DownloadClass();

dd.StrUrl = "http://127.0.0.1/1.rar";

dd.StrFileName="C:\\1.rar";

dd.DownloadFile();

Response.Write(dd.strError);

}

//测试用线程1断点续传下载网络上的文件到本地电脑

public class DownloadClass

{

public string StrUrl;//文件下载网址

public string StrFileName;//下载文件保存地址

public string strError;//返回结果

public long lStartPos = 0; //返回上次下载字节

public long lCurrentPos = 0;//返回当前下载字节

public long lDownloadFile;//返回当前下载文件长度

public void DownloadFile()

{

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);

long length = request.GetResponse().ContentLength;

lDownloadFile = length;

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);

lCurrentPos = fs.Length;

}

fs.Close();

ns.Close();

strError = "下载完成";

}

catch (Exception ex)

{

fs.Close();

strError = "下载过程中出现错误:" + ex.ToString();

}

}

}　

}