借助HttpWebRequest 调用第三方接口，获取Token和数据

在一次项目中，在给客户做系统时，需要调用客户的系统获取数据，客户提供了获取Token和获取数据的接口，用户名和密码，认证方式是基于Bearer的，通过学习和找资料，提供一个C#示例

一个C#示例

1、传入语句获取数据

         /// <summary>         /// 传入语句获取数据         /// </summary>         /// <param name="param"></param>         /// <returns></returns>         public async Task<string> ThirdSystemDataPostAsync(string param,string dataUrlAddress)         {             string token = await Bearer_TokenPostAsync();             _logger.Warn($"获取Token结构：{token}");             string responseString = string.Empty;             try             {                 var tokenJson = JsonConvert.DeserializeObject<TokenResultDto>(token);                 _logger.Warn($"获取Token值参数据：{tokenJson}");                  //跳过ssl验证                 ServicePointManager.ServerCertificateValidationCallback = (sender, certificate, chain, sslPolicyErrors) => true;                 // 创建HttpWebRequest对象                 HttpWebRequest httpRequest = (HttpWebRequest)WebRequest.Create(dataUrlAddress);                 _logger.Warn($"入参数据：{param}");                 _logger.Warn($"智慧系统数据地址：{dataUrlAddress}");                 // 设置Post调⽤⽅法                 httpRequest.Method = "Post";                 //设置参数传输类型                 httpRequest.ContentType = " application/json; charset=utf-8";                 // 设置Http Bearer认证的请求头                 httpRequest.Headers.Add("Authorization", "Bearer " + tokenJson.accessToken);                 //传输参数格式转换                 byte[] bytesRequestData = Encoding.UTF8.GetBytes(param);                 //_logger.Warn($"入参数据格式转换：{bytesRequestData}");                 httpRequest.ContentLength = bytesRequestData.Length;                 Stream postStream = await httpRequest.GetRequestStreamAsync();                 postStream.Write(bytesRequestData, 0, bytesRequestData.Length);                 postStream.Close();                 //获取设置身份认证及请求超时时间                 SetWebRequest(httpRequest);                 // HttpWebRequest发起调⽤                 using (HttpWebResponse myResponse = (HttpWebResponse)httpRequest.GetResponse())                 {                     //myResponse.StatusCode                     // StreamReader对象                     StreamReader sr = new StreamReader(myResponse.GetResponseStream(), Encoding.UTF8);                      // 返回结果                     responseString = sr.ReadToEnd();                      _logger.Warn($"调用智慧系统返回结果数据：{responseString}");                     return responseString;                 }             }             catch (Exception ex)             {                 //返回错误信息                 responseString = ex.ToString();             }             return responseString;          } 

2、获取token

         /// <summary>         /// 获取token         /// </summary>         /// <returns></returns>         private async Task<string> Bearer_TokenPostAsync(string sSoUrlAddress,string userName,string userPassword)         {             string responseString = string.Empty;             try             {                 // 创建HttpWebRequest对象                 HttpWebRequest httpRequest = (HttpWebRequest)WebRequest.Create(sSoUrlAddress);                 _logger.Warn($"智慧系统Token地址：{sSoUrlAddress}");                 // 设置Post调⽤⽅法                 httpRequest.Method = "Post";                 //设置参数传输类型                 httpRequest.ContentType = " application/json; charset=utf-8";                 // 设置用户名和密码                 var usermesg = new UserMesgInput()                 {                     Username = userName,                     Password = userPassword,                     UserDetail = true                 };                 string base64 = JsonConvert.SerializeObject(usermesg);                 //传输参数格式转换                 byte[] bytesRequestData = Encoding.UTF8.GetBytes(base64);                 //_logger.Warn($"入参数据格式转换：{bytesRequestData}");                 httpRequest.ContentLength = bytesRequestData.Length;                  Stream postStream = await httpRequest.GetRequestStreamAsync();                 postStream.Write(bytesRequestData, 0, bytesRequestData.Length);                  postStream.Close();                 //获取设置身份认证及请求超时时间                 SetWebRequest(httpRequest);                 _logger.Warn($"获取设置身份认证及请求超时时间");                 // HttpWebRequest发起调⽤                 using (HttpWebResponse myResponse = (HttpWebResponse)httpRequest.GetResponse())                 {                     _logger.Warn($"StreamReader对象");                     // StreamReader对象                     StreamReader sr = new StreamReader(myResponse.GetResponseStream(), Encoding.UTF8);                     //_logger.Warn($"返回结果{sr.ReadToEnd()}");                     // 返回结果                     responseString = sr.ReadToEnd();                                        _logger.Warn($"调用智慧系统返回结果Token：{responseString}");                     //return responseString;                 }             }             catch (Exception ex)             {                 //返回错误信息                 responseString = ex.ToString();             }             return responseString;         } 

3、获取设置身份认证及请求超时时间

        /// <summary>         /// 获取设置身份认证及请求超时时间         /// </summary>         /// <param name="request"></param>         private static void SetWebRequest(HttpWebRequest request)         {             request.Credentials = CredentialCache.DefaultCredentials;             request.Timeout = 1000000;          } 

4、在我使用的时候出现了下面的错误，通过查找是证书的问题，因为客户的web访问使用的IP地址访问，所以在代码中要加入跳过ssl验证的一行代码

System.Net.WebException: The SSL connection could not be established, see inner exception. The remote certificate is invalid according to the validation procedure.