WebApi现在越来越流行，下面给出利用HttpWebRequest访问WebApi的工具方法：
1、利用基准URL和参数字典生成完整URL
/// <summary> /// 生成URL字符串 /// </summary> /// <param name="baseUrl">基准URL</param> /// <param name="dictParam">参数字典</param> /// <returns>最终URL字符串</returns> public static string GetUrl(string baseUrl, Dictionary<string, string> dictParam) { if (string.IsNullOrWhiteSpace(baseUrl)) { throw new ArgumentNullException("baseUrl", "基准URL不能为空"); } StringBuilder sbParam = new StringBuilder(); string strParam = string.Empty; if (dictParam != null && dictParam.Count > 0) { sbParam.Append("?"); foreach (KeyValuePair<string, string> item in dictParam) { sbParam.Append(string.Format("{0}={1}&", item.Key, HttpUtility.UrlEncode(item.Value, Encoding.UTF8))); } strParam = sbParam.ToString(); strParam = strParam.Substring(0, strParam.Length - 1); } string strUrl = string.Format("{0}{1}", baseUrl, strParam); return strUrl; }
2、通过HTTP请求获取数据（参数为非model类型）
/// <summary> /// 通过http请求获取数据(参数为非model类型) /// </summary> /// <param name="url">获取数据的url</param> /// <param name="requestMethod">请求方法：GET/POST/PUT/DELETE</param> /// <param name="jsonData">返回的json数据</param> /// <param name="errMsg">错误信息</param> /// <returns>true：成功 false：失败</returns> public static bool RequestHttpData(string url, string requestMethod, out string jsonData, out string errMsg) { jsonData = string.Empty; errMsg = string.Empty; string result = string.Empty; try { //创建请求 HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest; request.Timeout = 15 * 60 * 1000; //15分钟 request.Method = requestMethod; request.KeepAlive = true; request.AllowAutoRedirect = false; //获取数据 using (HttpWebResponse response = request.GetResponse() as HttpWebResponse) { StreamReader sr = new StreamReader(response.GetResponseStream()); result = sr.ReadToEnd(); } } catch (WebException ex) { try { WebResponse wr = ex.Response; Stream st = wr.GetResponseStream(); StreamReader sr = new StreamReader(st, System.Text.Encoding.Default); string tmpErr = sr.ReadToEnd(); Regex r = new Regex(@"<body><h1>.*</h1>"); errMsg = r.Match(tmpErr).Value.Replace("<body><h1>", "").Replace("</h1>", ""); sr.Close(); st.Close(); } catch { errMsg = ex.Message; } return false; } catch (Exception ex) { errMsg = ex.Message; return false; } if (!string.IsNullOrWhiteSpace(result)) { jsonData = result; } return true; }
3、通过HTTP请求获取数据（参数为model类型）
/// <summary> /// 通过http请求传递数据（参数为model类型） /// </summary> /// <param name="url">传递数据的url</param> /// <param name="paraJson">要传递的Json数据</param> /// <param name="requestMethod">请求方法：GET/POST/PUT/DELETE</param> /// <param name="jsonData">返回的json数据</param> /// <param name="errMsg">错误信息</param> /// <returns>true：成功 false：失败</returns> public static bool RequestHttpData(string url, string paraJson, string requestMethod, out string jsonData, out string errMsg) { jsonData = string.Empty; errMsg = string.Empty; string result = string.Empty; try { HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest; request.Timeout = 15 * 60 * 1000; //15分钟 request.Method = requestMethod; request.KeepAlive = true; request.AllowAutoRedirect = false; request.ContentType = "application/json"; byte[] postdatabtyes = Encoding.UTF8.GetBytes(paraJson); request.ContentLength = postdatabtyes.Length; Stream requeststream = request.GetRequestStream(); requeststream.Write(postdatabtyes, 0, postdatabtyes.Length); requeststream.Close(); using (HttpWebResponse response = request.GetResponse() as HttpWebResponse) { StreamReader sr = new StreamReader(response.GetResponseStream(), Encoding.UTF8); result = sr.ReadToEnd(); } } catch (WebException ex) { try { WebResponse wr = ex.Response; Stream st = wr.GetResponseStream(); StreamReader sr = new StreamReader(st, System.Text.Encoding.Default); string tmpErr = sr.ReadToEnd(); Regex r = new Regex(@"<body><h1>.*</h1>"); errMsg = r.Match(tmpErr).Value.Replace("<body><h1>", "").Replace("</h1>", ""); sr.Close(); st.Close(); } catch { errMsg = ex.Message; } return false; } catch (Exception ex) { errMsg = ex.Message; return false; } if (!string.IsNullOrWhiteSpace(result)) { jsonData = result; } return true; }