转载:http://blog.csdn.net/kevonz/article/details/5078432
using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Windows.Forms; using System.Net; using System.IO; namespace The9web.Com { class UpDownLoadFile { /// <summary> /// WebClient上传文件至服务器(不带进度条) /// </summary> /// <param name="fileNameFullPath">要上传的文件(全路径格式)</param> /// <param name="strUrlDirPath">Web服务器文件夹路径</param> /// <returns>True/False是否上传成功</returns> public bool UpLoadFile(string fileNameFullPath, string strUrlDirPath) { //得到要上传的文件文件名 string fileName = fileNameFullPath.Substring(fileNameFullPath.LastIndexOf("//") + 1); //新文件名由年月日时分秒及毫秒组成 string NewFileName = DateTime.Now.ToString("yyyyMMddhhmmss") + DateTime.Now.Millisecond.ToString() + fileNameFullPath.Substring(fileNameFullPath.LastIndexOf(".")); //得到文件扩展名 string fileNameExt = fileName.Substring(fileName.LastIndexOf(".") + 1); if (strUrlDirPath.EndsWith("/") == false) strUrlDirPath = strUrlDirPath + "/"; //保存在服务器上时,将文件改名(示业务需要) strUrlDirPath = strUrlDirPath + NewFileName; // 创建WebClient实例 WebClient myWebClient = new WebClient(); myWebClient.Credentials = CredentialCache.DefaultCredentials; // 将要上传的文件打开读进文件流 FileStream myFileStream = new FileStream(fileNameFullPath, FileMode.Open, FileAccess.Read); BinaryReader myBinaryReader = new BinaryReader(myFileStream); try { byte[] postArray = myBinaryReader.ReadBytes((int)myFileStream.Length); //打开远程Web地址,将文件流写入 Stream postStream = myWebClient.OpenWrite(strUrlDirPath, "PUT"); if (postStream.CanWrite) { postStream.Write(postArray, 0, postArray.Length); } else { //MessageBox.Show("Web服务器文件目前不可写入,请检查Web服务器目录权限设置!","系统提示",MessageBoxButtons.OK,MessageBoxIcon.Information); } postStream.Close();//关闭流 return true; } catch (Exception exp) { //MessageBox.Show("文件上传失败:" + exp.Message, "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Information); return false; } } /// <summary> /// 下载服务器文件至客户端(不带进度条) /// </summary> /// <param name="strUrlFilePath">要下载的Web服务器上的文件地址(全路径 如:http://www.the9web.com/test.rar)</param> /// <param name="Dir">下载到的目录(存放位置,机地机器文件夹)</param> /// <returns>True/False是否上传成功</returns> public bool DownLoadFile(string strUrlFilePath, string strLocalDirPath) { // 创建WebClient实例 WebClient client = new WebClient(); //被下载的文件名 string fileName = strUrlFilePath.Substring(strUrlFilePath.LastIndexOf("/")); //另存为的绝对路径+文件名 string Path = strLocalDirPath + fileName; try { WebRequest myWebRequest = WebRequest.Create(strUrlFilePath); } catch (Exception exp) { MessageBox.Show("文件下载失败:" + exp.Message, "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Information); } try { client.DownloadFile(strUrlFilePath, Path); return true; } catch (Exception exp) { MessageBox.Show("文件下载失败:" + exp.Message, "系统提示", MessageBoxButtons.OK, MessageBoxIcon.Information); return false; } } /// <summary> /// 下载带进度条代码(普通进度条) /// </summary> /// <param name="URL">网址</param> /// <param name="Filename">文件名</param> /// <param name="Prog">普通进度条ProgressBar</param> /// <returns>True/False是否下载成功</returns> public bool DownLoadFile(string URL, string Filename, ProgressBar Prog) { try { System.Net.HttpWebRequest Myrq = (System.Net.HttpWebRequest)System.Net.HttpWebRequest.Create(URL); //从URL地址得到一个WEB请求 System.Net.HttpWebResponse myrp = (System.Net.HttpWebResponse)Myrq.GetResponse(); //从WEB请求得到WEB响应 long totalBytes = myrp.ContentLength; //从WEB响应得到总字节数 Prog.Maximum = (int)totalBytes; //从总字节数得到进度条的最大值 System.IO.Stream st = myrp.GetResponseStream(); //从WEB请求创建流(读) System.IO.Stream so = new System.IO.FileStream(Filename, System.IO.FileMode.Create); //创建文件流(写) long totalDownloadedByte = 0; //下载文件大小 byte[] by = new byte[1024]; int osize = st.Read(by, 0, (int)by.Length); //读流 while (osize > 0) { totalDownloadedByte = osize + totalDownloadedByte; //更新文件大小 Application.DoEvents(); so.Write(by, 0, osize); //写流 Prog.Value = (int)totalDownloadedByte; //更新进度条 osize = st.Read(by, 0, (int)by.Length); //读流 } so.Close(); //关闭流 st.Close(); //关闭流 return true; } catch { return false; } } /// <summary> /// 下载带进度条代码(状态栏式进度条) /// </summary> /// <param name="URL">网址</param> /// <param name="Filename">文件名</param> /// <param name="Prog">状态栏式进度条ToolStripProgressBar</param> /// <returns>True/False是否下载成功</returns> public bool DownLoadFile(string URL, string Filename, ToolStripProgressBar Prog) { try { System.Net.HttpWebRequest Myrq = (System.Net.HttpWebRequest)System.Net.HttpWebRequest.Create(URL); //从URL地址得到一个WEB请求 System.Net.HttpWebResponse myrp = (System.Net.HttpWebResponse)Myrq.GetResponse(); //从WEB请求得到WEB响应 long totalBytes = myrp.ContentLength; //从WEB响应得到总字节数 Prog.Maximum = (int)totalBytes; //从总字节数得到进度条的最大值 System.IO.Stream st = myrp.GetResponseStream(); //从WEB请求创建流(读) System.IO.Stream so = new System.IO.FileStream(Filename, System.IO.FileMode.Create); //创建文件流(写) long totalDownloadedByte = 0; //下载文件大小 byte[] by = new byte[1024]; int osize = st.Read(by, 0, (int)by.Length); //读流 while (osize > 0) { totalDownloadedByte = osize + totalDownloadedByte; //更新文件大小 Application.DoEvents(); so.Write(by, 0, osize); //写流 Prog.Value = (int)totalDownloadedByte; //更新进度条 osize = st.Read(by, 0, (int)by.Length); //读流 } so.Close(); //关闭流 st.Close(); //关闭流 return true; } catch { return false; } } } }
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WebClient还有一个十分酷的特性,可惜官方帮助没有提及。WebClient可以与浏览器共享缓存文件!具体说来,如果你通过网页浏览已经缓存了某个文件,当你用WebClient下载这个文件时,WebClient会直接从缓存文件中直接读取,不再重新下载。反之亦然,WebClient下载的文件会保存在浏览器缓存目录中,供浏览器和WebClient下次使用。这可是实现silverlight动态下载并缓存的理论基础,十分重要!!
当然有些时候开发者并不想使用缓存文件。例如服务器文件更新了,希望下载最新的文件而不是缓存的文件。这种情况怎么处理呢?有人提出了一个解决办法:因为文件缓存是基于url的,如果在url后面加上一些随机的无意义的字符,例如?o=123,则可绕过缓存。缺点是每次下载都会增加新的缓存文件,浪费空
使用WebClient实现文件下载
http://blog.sina.com.cn/s/blog_6e51df7f0100sw6t.html
时间: 2024-10-22 11:22:51