C# Http访问帮助类，支持get post请求文件下载 [
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using System; using System.Collections.Generic; using System.Collections.Specialized; using System.IO; using System.Linq; using System.Net; using System.Text; namespace XX.Common.Http { /// <summary> /// Http访问帮助类 /// </summary> public class HttpHelper { /// <summary> /// HttpWebRequest 通过Post /// </summary> /// <param name="url">URI</param> /// <param name="postData">post数据</param> /// <returns></returns> public static string PostDataGethtml(string url, string postData) { try { byte[] data = Encoding.UTF8.GetBytes(postData); Uri uri = new Uri(url); HttpWebRequest req = WebRequest.Create(uri) as HttpWebRequest; if (req == null) { return "Network error:" + new ArgumentNullException("httpWebRequest").Message; } req.Method = "POST"; req.KeepAlive = true; req.ContentType = "application/x-www-form-urlencoded"; req.ContentLength = data.Length; req.AllowAutoRedirect = true; Stream outStream = req.GetRequestStream(); outStream.Write(data, 0, data.Length); outStream.Close(); var res = req.GetResponse() as HttpWebResponse; if (res == null) { return "Network error:" + new ArgumentNullException("HttpWebResponse").Message; } Stream inStream = res.GetResponseStream(); var sr = new StreamReader(inStream, Encoding.UTF8); string htmlResult = sr.ReadToEnd(); return htmlResult; } catch (Exception ex) { return "网络错误(Network error)：" + ex.Message; } } /// <summary> /// HttpWebRequest 通过get /// </summary> /// <param name="url">URI</param> /// <returns></returns> public static string GetDataGetHtml(string url) { try { HttpWebRequest httpWebRequest = (HttpWebRequest)WebRequest.Create(url); httpWebRequest.ContentType = "application/x-www-form-urlencoded"; httpWebRequest.Method = "GET"; //对发送的数据不使用缓存 httpWebRequest.AllowWriteStreamBuffering = false; httpWebRequest.Timeout = 300000; httpWebRequest.ServicePoint.Expect100Continue = false; HttpWebResponse webRespon = (HttpWebResponse)httpWebRequest.GetResponse(); Stream webStream = webRespon.GetResponseStream(); if (webStream == null) { return "网络错误(Network error)：" + new ArgumentNullException("webStream"); } StreamReader streamReader = new StreamReader(webStream, Encoding.UTF8); string responseContent = streamReader.ReadToEnd(); webRespon.Close(); streamReader.Close(); return responseContent; } catch (Exception ex) { return "网络错误(Network error)：" + ex.Message; } } /// <summary> /// HttpWebRequest 通过get /// </summary> /// <param name="url">URI</param> /// <returns></returns> public static bool GetDataGetHtml(string url, string filePath,ref string mg) { try { HttpWebRequest httpWebRequest = (HttpWebRequest)WebRequest.Create(url); httpWebRequest.ContentType = "application/x-www-form-urlencoded"; httpWebRequest.Method = "GET"; //对发送的数据不使用缓存 httpWebRequest.AllowWriteStreamBuffering = false; httpWebRequest.Timeout = 300000; httpWebRequest.ServicePoint.Expect100Continue = false; HttpWebResponse webRespon = (HttpWebResponse)httpWebRequest.GetResponse(); Stream webStream = webRespon.GetResponseStream(); if (webStream == null) { return false; } StreamReader streamReader = new StreamReader(webStream, Encoding.UTF8); string responseContent = streamReader.ReadToEnd(); mg = responseContent; webRespon.Close(); streamReader.Close(); if (responseContent.ToUpper().IndexOf("NULL") > -1) { return false; } else { FileStream fs = new FileStream(filePath, FileMode.Create); var buff = Encoding.UTF8.GetBytes(responseContent); fs.Write(buff, buff.Length, 0); fs.Close(); return true; } } catch (Exception ex) { return false; } } /// <summary> /// 将本地文件上传到指定的服务器(HttpWebRequest方法) /// </summary> /// <param name="address">文件上传到的服务器</param> /// <param name="fileNamePath">要上传的本地文件（全路径）</param> /// <param name="saveName">文件上传后的名称</param> /// <returns>成功返回1，失败返回0</returns> public static int Upload_Request(string address, string fileNamePath, string saveName) { // 要上传的文件 try { if (!File.Exists(fileNamePath)) { return 0; } FileStream fs = new FileStream(fileNamePath, FileMode.Open, FileAccess.Read); return Upload_Request(address, fs, saveName); } catch (Exception ex) { return 0; } } /// <summary> /// 将本地文件流上传到指定的服务器(HttpWebRequest方法) /// </summary> /// <param name="address">文件上传到的服务器</param> /// <param name="fileStream">要上传的本地文件流</param> /// <param name="saveName">文件上传后的名称</param> /// <returns>成功返回1，失败返回0</returns> public static int Upload_Request(string address, Stream fileStream, string saveName) { int returnValue = 0; fileStream.Position = 0; var r = new BinaryReader(fileStream); //时间戳 string strBoundary = "----------" + DateTime.Now.Ticks.ToString("x"); byte[] boundaryBytes = Encoding.ASCII.GetBytes("\r\n--" + strBoundary + "\r\n"); //请求头部信息 StringBuilder sb = new StringBuilder(); sb.Append("--"); sb.Append(strBoundary); sb.Append("\r\n"); sb.Append("Content-Disposition: form-data; name=\""); sb.Append("file"); sb.Append("\"; filename=\""); sb.Append(saveName); sb.Append("\""); sb.Append("\r\n"); sb.Append("Content-Type: "); sb.Append("application/octet-stream"); sb.Append("\r\n"); sb.Append("\r\n"); string strPostHeader = sb.ToString(); byte[] postHeaderBytes = Encoding.UTF8.GetBytes(strPostHeader); try { // 根据uri创建HttpWebRequest对象 HttpWebRequest httpReq = (HttpWebRequest)WebRequest.Create(new Uri(address)); httpReq.Method = "POST"; //对发送的数据不使用缓存 httpReq.AllowWriteStreamBuffering = false; //设置获得响应的超时时间（300秒） httpReq.Timeout = 300000; httpReq.ServicePoint.Expect100Continue = false; httpReq.ContentType = "multipart/form-data; boundary=" + strBoundary; long length = fileStream.Length + postHeaderBytes.Length + boundaryBytes.Length; long fileLength = fileStream.Length; httpReq.ContentLength = length; byte[] buffer = new byte[fileLength]; Stream postStream = httpReq.GetRequestStream(); //发送请求头部消息 postStream.Write(postHeaderBytes, 0, postHeaderBytes.Length); int size = r.Read(buffer, 0, buffer.Length); postStream.Write(buffer, 0, size); //添加尾部的时间戳 postStream.Write(boundaryBytes, 0, boundaryBytes.Length); postStream.Close(); //获取服务器端的响应 HttpWebResponse webRespon = (HttpWebResponse)httpReq.GetResponse(); if (webRespon.StatusCode == HttpStatusCode.OK) //如果服务器未响应，那么继续等待相应 { Stream s = webRespon.GetResponseStream(); StreamReader sr = new StreamReader(s); //读取服务器端返回的消息 String sReturnString = sr.ReadLine(); s.Close(); sr.Close(); fileStream.Close(); if (sReturnString == "Success") { returnValue = 1; } else { returnValue = 0; } } } catch (Exception ex) { returnValue = 0; } return returnValue; } /// <summary> /// 将本地文件上传到指定服务器上（HttpWebRequest方法），并传递相应参数 /// </summary> /// <param name="url">文件上传到的服务器</param> /// <param name="fileKeyName">类型（此处为文件--file）</param> /// <param name="filePath">要上传的本地文件（全路径）</param> /// <param name="filename">文件上传后的名称</param> /// <param name="stringDict">参数集合</param> /// <param name="timeOut">请求时效</param> /// <returns></returns> public static string HttpPostData(string url, string fileKeyName, string filePath, string filename, NameValueCollection stringDict, int timeOut = 900000) { string responseContent; try { var memStream = new MemoryStream(); var webRequest = (HttpWebRequest)WebRequest.Create(url); // 边界符 var boundary = "---------------" + DateTime.Now.Ticks.ToString("x"); // 边界符 var beginBoundary = Encoding.ASCII.GetBytes("--" + boundary + "\r\n"); var fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read); // 最后的结束符 var endBoundary = Encoding.ASCII.GetBytes("--" + boundary + "--\r\n"); // 设置属性 webRequest.Method = "POST"; webRequest.Timeout = timeOut; webRequest.ContentType = "multipart/form-data; boundary=" + boundary; // 写入文件 const string filePartHeader = "Content-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"\r\n" + "Content-Type: application/octet-stream\r\n\r\n"; var header = string.Format(filePartHeader, fileKeyName, filename); var headerbytes = Encoding.UTF8.GetBytes(header); memStream.Write(beginBoundary, 0, beginBoundary.Length); memStream.Write(headerbytes, 0, headerbytes.Length); var buffer = new byte[1024]; int bytesRead; // =0 while ((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0) { memStream.Write(buffer, 0, bytesRead); } // 写入字符串的Key var stringKeyHeader = "\r\n--" + boundary + "\r\nContent-Disposition: form-data; name=\"{0}\"" + "\r\n\r\n{1}\r\n"; foreach (byte[] formitembytes in from string key in stringDict.Keys select string.Format(stringKeyHeader, key, stringDict[key]) into formitem select Encoding.UTF8.GetBytes(formitem)) { memStream.Write(formitembytes, 0, formitembytes.Length); } // 写入最后的结束边界符 memStream.Write(endBoundary, 0, endBoundary.Length); webRequest.ContentLength = memStream.Length; var requestStream = webRequest.GetRequestStream(); memStream.Position = 0; var tempBuffer = new byte[memStream.Length]; memStream.Read(tempBuffer, 0, tempBuffer.Length); memStream.Close(); requestStream.Write(tempBuffer, 0, tempBuffer.Length); requestStream.Close(); var httpWebResponse = (HttpWebResponse)webRequest.GetResponse(); using (var httpStreamReader = new StreamReader(httpWebResponse.GetResponseStream(), Encoding.GetEncoding("utf-8"))) { responseContent = httpStreamReader.ReadToEnd(); } fileStream.Close(); httpWebResponse.Close(); webRequest.Abort(); } catch (Exception ex) { responseContent = ex.Message; } return responseContent; } /// <summary> /// Http下载文件支持断点续传 /// </summary> /// <param name="uri">下载地址</param> /// <param name="filefullpath">存放完整路径（含文件名）</param> /// <param name="size">每次多的大小</param> /// <returns>下载操作是否成功</returns> public static bool HttpDownLoadFiles(string uri, string filefullpath, int size = 1024) { try { string fileDirectory = System.IO.Path.GetDirectoryName(filefullpath); if (!Directory.Exists(fileDirectory)) { Directory.CreateDirectory(fileDirectory); } string fileFullPath = filefullpath; string fileTempFullPath = filefullpath + ".tmp"; if (File.Exists(fileFullPath)) { return true; } else { if (File.Exists(fileTempFullPath)) { FileStream fs = new FileStream(fileTempFullPath, FileMode.Append, FileAccess.Write, FileShare.ReadWrite); byte[] buffer = new byte[512]; HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(uri); request.Timeout = 10000; request.AddRange((int)fs.Length); Stream ns = request.GetResponse().GetResponseStream(); long contentLength = request.GetResponse().ContentLength; int length = ns.Read(buffer, 0, buffer.Length); while (length > 0) { fs.Write(buffer, 0, length); buffer = new byte[512]; length = ns.Read(buffer, 0, buffer.Length); } fs.Close(); File.Move(fileTempFullPath, fileFullPath); } else { FileStream fs = new FileStream(fileTempFullPath, FileMode.Create); byte[] buffer = new byte[512]; HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(uri); request.Timeout = 10000; request.AddRange((int)fs.Length); Stream ns = request.GetResponse().GetResponseStream(); long contentLength = request.GetResponse().ContentLength; int length = ns.Read(buffer, 0, buffer.Length); while (length > 0) { fs.Write(buffer, 0, length); buffer = new byte[512]; length = ns.Read(buffer, 0, buffer.Length); } fs.Close(); File.Move(fileTempFullPath, fileFullPath); } return true; } } catch (Exception ex) { return false; } } /// <summary> /// Http下载文件 /// </summary> /// <param name="uri">下载地址</param> /// <param name="filefullpath">存放完整路径（含文件名）</param> /// <param name="size">每次多的大小</param> /// <returns>下载操作是否成功</returns> public static bool DownLoadFiles(string uri, string filefullpath,int size=1024) { try { if (File.Exists(filefullpath)) { try { File.Delete(filefullpath); } catch (Exception ex) { return false; } } string fileDirectory = System.IO.Path.GetDirectoryName(filefullpath); if (!Directory.Exists(fileDirectory)) { Directory.CreateDirectory(fileDirectory); } FileStream fs = new FileStream(filefullpath, FileMode.Create); byte[] buffer = new byte[size]; HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(uri); request.Timeout = 10000; request.AddRange((int)fs.Length); Stream ns = request.GetResponse().GetResponseStream(); long contentLength = request.GetResponse().ContentLength; int length = ns.Read(buffer, 0, buffer.Length); while (length > 0) { fs.Write(buffer, 0, length); buffer = new byte[size]; length = ns.Read(buffer, 0, buffer.Length); } fs.Close(); return true; } catch (Exception ex) { return false; } } } }
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