C# HttpWebRequest 后台調用接口上傳大文件以及其他參數

直接上代碼，包各位看客能用！！！

1.首先請求參數的封裝

/// <summary>
    /// 上傳文件 - 請求參數類
    /// </summary>
    public class UploadParameterType
    {
        public UploadParameterType()
        {
            FileNameKey = "fileName";
            Encoding = Encoding.UTF8;
            PostParameters = new Dictionary<string, string>();
        }
        /// <summary>
        /// 上傳地址
        /// </summary>
        public string Url { get; set; }
        /// <summary>
        /// 文件名稱key
        /// </summary>
        public string FileNameKey { get; set; }
        /// <summary>
        /// 文件名稱value
        /// </summary>
        public string FileNameValue { get; set; }
        /// <summary>
        /// 編碼格式
        /// </summary>
        public Encoding Encoding { get; set; }
        /// <summary>
        /// 上傳文件的流
        /// </summary>
        public Stream UploadStream { get; set; }
        /// <summary>
        /// 上傳文件 攜帶的參數集合
        /// </summary>
        public IDictionary<string, string> PostParameters { get; set; }
    }

　　2.HttpWebRequest 封裝

/// <summary>
    /// Http上傳文件類 - HttpWebRequest封裝
    /// </summary>
    public class HttpUploadClient
    {
        /// <summary>
        /// 上傳執行 方法
        /// </summary>
        /// <param name="parameter">上傳文件請求參數</param>
        public static string Execute(UploadParameterType parameter)
        {
            using (MemoryStream memoryStream = new MemoryStream())
            {
                // 1.分界線
                string boundary = string.Format("----{0}", DateTime.Now.Ticks.ToString("x")),       // 分界線可以自定義參數
                    beginBoundary = string.Format("--{0}\r\n", boundary),
                    endBoundary = string.Format("\r\n--{0}--\r\n", boundary);
                byte[] beginBoundaryBytes = parameter.Encoding.GetBytes(beginBoundary),
                    endBoundaryBytes = parameter.Encoding.GetBytes(endBoundary);
                // 2.組裝開始分界線數據體 到內存流中
                memoryStream.Write(beginBoundaryBytes, 0, beginBoundaryBytes.Length);
                // 3.組裝 上傳文件附加攜帶的參數 到內存流中
                if (parameter.PostParameters != null && parameter.PostParameters.Count > 0)
                {
                    foreach (KeyValuePair<string, string> keyValuePair in parameter.PostParameters)
                    {
                        string parameterHeaderTemplate = string.Format("Content-Disposition: form-data; name=\"{0}\"\r\n\r\n{1}\r\n{2}", keyValuePair.Key, keyValuePair.Value, beginBoundary);
                        byte[] parameterHeaderBytes = parameter.Encoding.GetBytes(parameterHeaderTemplate);

                        memoryStream.Write(parameterHeaderBytes, 0, parameterHeaderBytes.Length);
                    }
                }
                // 4.組裝文件頭數據體 到內存流中
                string fileHeaderTemplate = string.Format("Content-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"\r\nContent-Type: application/octet-stream\r\n\r\n", parameter.FileNameKey, parameter.FileNameValue);
                byte[] fileHeaderBytes = parameter.Encoding.GetBytes(fileHeaderTemplate);
                memoryStream.Write(fileHeaderBytes, 0, fileHeaderBytes.Length);
                // 5.組裝文件流 到內存流中
                byte[] buffer = new byte[1024 * 1024 * 1];
                int size = parameter.UploadStream.Read(buffer, 0, buffer.Length);
                while (size > 0)
                {
                    memoryStream.Write(buffer, 0, size);
                    size = parameter.UploadStream.Read(buffer, 0, buffer.Length);
                }
                // 6.組裝結束分界線數據體 到內存流中
                memoryStream.Write(endBoundaryBytes, 0, endBoundaryBytes.Length);
                // 7.獲取二進制數據
                byte[] postBytes = memoryStream.ToArray();
                memoryStream.Close();
                GC.Collect();
                // 8.HttpWebRequest 組裝
                HttpWebRequest webRequest = (HttpWebRequest)WebRequest.Create(new Uri(parameter.Url, UriKind.RelativeOrAbsolute));
                webRequest.AllowWriteStreamBuffering = false;
                webRequest.Method = "POST";
                webRequest.Timeout = 1800000;
                webRequest.ContentType = string.Format("multipart/form-data; boundary={0}", boundary);
                webRequest.ContentLength = postBytes.Length;
                if (Regex.IsMatch(parameter.Url, "^https://"))
                {
                    ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls;
                    ServicePointManager.ServerCertificateValidationCallback = CheckValidationResult;
                }
                // 9.寫入上傳請求數據
                using (Stream requestStream = webRequest.GetRequestStream())
                {
                    requestStream.Write(postBytes, 0, postBytes.Length);
                    requestStream.Close();
                }
                // 10.獲取響應
                using (HttpWebResponse webResponse = (HttpWebResponse)webRequest.GetResponse())
                {
                    using (StreamReader reader = new StreamReader(webResponse.GetResponseStream(), parameter.Encoding))
                    {
                        string body = reader.ReadToEnd();
                        reader.Close();
                        return body;
                    }
                }
            }
        }
        /// <summary>
        /// 上傳執行 方法
        /// </summary>
        /// <param name="parameter">上傳文件請求參數</param>
        public static string Execute2(UploadParameterType parameter)
        {
            // 1.分界線
            string boundary = string.Format("----{0}", DateTime.Now.Ticks.ToString("x")),       // 分界線可以自定義參數
                beginBoundary = string.Format("--{0}\r\n", boundary),
                endBoundary = string.Format("\r\n--{0}--\r\n", boundary);
            byte[] beginBoundaryBytes = parameter.Encoding.GetBytes(beginBoundary),
                endBoundaryBytes = parameter.Encoding.GetBytes(endBoundary);
            byte[] postBytes = new byte[] { };
            using (MemoryStream memoryStream = new MemoryStream())
            {
                // 2.組裝開始分界線數據體 到內存流中
                memoryStream.Write(beginBoundaryBytes, 0, beginBoundaryBytes.Length);
                // 3.組裝 上傳文件附加攜帶的參數 到內存流中
                if (parameter.PostParameters != null && parameter.PostParameters.Count > 0)
                {
                    foreach (KeyValuePair<string, string> keyValuePair in parameter.PostParameters)
                    {
                        string parameterHeaderTemplate = string.Format("Content-Disposition: form-data; name=\"{0}\"\r\n\r\n{1}\r\n{2}", keyValuePair.Key, keyValuePair.Value, beginBoundary);
                        byte[] parameterHeaderBytes = parameter.Encoding.GetBytes(parameterHeaderTemplate);
                        memoryStream.Write(parameterHeaderBytes, 0, parameterHeaderBytes.Length);
                    }
                }
                // 4.組裝文件頭數據體 到內存流中
                string fileHeaderTemplate = string.Format("Content-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"\r\nContent-Type: application/octet-stream\r\n\r\n", parameter.FileNameKey, parameter.FileNameValue);
                byte[] fileHeaderBytes = parameter.Encoding.GetBytes(fileHeaderTemplate);
                memoryStream.Write(fileHeaderBytes, 0, fileHeaderBytes.Length);

                // 5.組裝結束分界線數據體 到內存流中
                //memoryStream.Write(endBoundaryBytes, 0, endBoundaryBytes.Length);
                // 6.獲取二進制數據
                postBytes = memoryStream.ToArray();
            }
            // 7.HttpWebRequest 組裝
            HttpWebRequest webRequest = (HttpWebRequest)WebRequest.Create(new Uri(parameter.Url, UriKind.RelativeOrAbsolute));
            //對發送的數據不使用緩存【重要、關鍵】
            webRequest.AllowWriteStreamBuffering = false;
            webRequest.Method = "POST";
            webRequest.Timeout = 1800000;
            webRequest.ContentType = string.Format("multipart/form-data; boundary={0}", boundary);
            webRequest.ContentLength = postBytes.Length + parameter.UploadStream.Length+endBoundaryBytes.Length;
            if (Regex.IsMatch(parameter.Url, "^https://"))
            {
                ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls;
                ServicePointManager.ServerCertificateValidationCallback = CheckValidationResult;
            }
            // 8.組裝文件流
            byte[] buffer = new byte[1024 * 1024 * 1];
            int size = parameter.UploadStream.Read(buffer, 0, buffer.Length);
            Stream requestStream = webRequest.GetRequestStream();
            requestStream.Write(postBytes, 0, postBytes.Length);
            while (size > 0)
            {
                requestStream.Write(buffer, 0, size);
                size = parameter.UploadStream.Read(buffer, 0, buffer.Length);
            }
            requestStream.Write(endBoundaryBytes, 0, endBoundaryBytes.Length);
            requestStream.Close();
            // 9.獲取響應
            using (HttpWebResponse webResponse = (HttpWebResponse)webRequest.GetResponse())
            {
                using (StreamReader reader = new StreamReader(webResponse.GetResponseStream(), parameter.Encoding))
                {
                    string body = reader.ReadToEnd();
                    reader.Close();
                    return body;
                }
            }
        }
        static bool CheckValidationResult(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors errors)
        {
            return true;
        }


    }

　　HttpUploadClient類中兩個Execute2，參考網上，大都用第一個，如果上傳小文件沒問題，要是比較大（百兆以上）就會內存溢出，然后就用流方式。思路是一樣的

3.調用示例：

            using (FileStream fs = new FileStream(@"C:\\test.zip", FileMode.Open, FileAccess.Read))
            {
                Dictionary<string, string> postParameter = new Dictionary<string, string>();
                postParameter.Add("name", "heshang");
                postParameter.Add("param", "1 2 3");
                string result = HttpUploadClient.Execute(new UploadParameterType
                {
                    Url = url,
                    UploadStream = fs,
                    FileNameValue = "test.zip",
                    PostParameters = postParameter
                });
            }

　　4.接口服務后台接受請求時：

public IHttpActionResult Post()
        {
            HttpPostedFile file = HttpContext.Current.Request.Files[0];
            string pyPath = HttpContext.Current.Request["name"];
            string Params = HttpContext.Current.Request["params"];
            file.SaveAs("C:\\test.zip");
            return Ok("");
        }

　　5.完美解決大文件上傳