c#发送请求访问外部接口的实例

我就废话不多说了，大家还是直接看代码吧~

 string url = "https://cloud.soei.com.cn/smsapi/sms/verifycode";
      HttpClient httpClient = new HttpClient();
      httpClient.BaseAddress = new Uri(url);
      //表头参数
      string token = "9c0025b4aae442bda5498971ec1ab219";
      httpClient.DefaultRequestHeaders.Add("token", token);
      httpClient.DefaultRequestHeaders.Accept.Clear();
      httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
      try
      {
        using (var request = new HttpRequestMessage())
        {
          var postBody = $"{{"identity":"{identity}","phoneNumber":"{phoneNumber}","code":"[code]"}}";
          request.Method = HttpMethod.Post;
          request.Content = new StringContent(postBody, Encoding.UTF8, "application/json");
          var response = await httpClient.SendAsync(request);
          //返回结果
          var retString = await response.Content.ReadAsStringAsync();
          JObject items = (JObject)JsonConvert.DeserializeObject(retString);
          //返回码，成功为200
          string retCode = items["code"].ToString();
          返回消息
          string message = items["message"].ToString();
          string data = items["data"].ToString();
          JObject items_data = (JObject)JsonConvert.DeserializeObject(data);
          string isSuccess = items_data["isSuccess"].ToString();
          string data_message = items_data["message"].ToString();
          if (isSuccess == "False")
          {
            retCode = "300";
          }
          retMessage.retCode = retCode;
          retMessage.message = data_message;
        }
      }
      catch (Exception e)
      {
        retMessage.retCode = "300";
        retMessage.message = e.Message.ToString();
      }
 
      return retMessage;
    }

 public static async Task<string> PostData(string path,string serverPath,dynamic param) {
      try
      {
        HttpClient client = new HttpClient();
      
        client.DefaultRequestHeaders.Add("Referer", string.Format("http://{0}", serverPath));
        HttpResponseMessage response;
        using (HttpContent httpContent = new StringContent(param, Encoding.UTF8))
        {
 
          
          httpContent.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("application/json");
          //client.DefaultRequestHeaders.Add("x-token", "M3Q_mQEwmn9l4Ly7fM7DxaMSdlYSSup5lfKLztF_VP97Urf");
          response = await client.PostAsync(path, httpContent).ContinueWith(res =>
          {
 
            return res;
 
          }).Result;
        }
        if (response != null && response.IsSuccessStatusCode)
        {
          return await response.Content.ReadAsStringAsync();
 
        }
        else
        {
          return string.Empty;
        }
      }
      catch (Exception ex)
      {
 
        throw;
      }
      finally
      {
      }
    }

补充：C#后台调用Http外网接口（GET, POST）

1.get方法调用接口获取json文件内容

public void GetFunction()
    {
      
      string serviceAddress = "http://222.111.999.444:8687/tttr/usercrd/12/b7e50cb45a?userid=9999";
      HttpWebRequest request = (HttpWebRequest)WebRequest.Create(serviceAddress);
      request.Method = "GET";
      request.ContentType = "text/html;charset=UTF-8";
      HttpWebResponse response = (HttpWebResponse)request.GetResponse();
      Stream myResponseStream = response.GetResponseStream();
      StreamReader myStreamReader = new StreamReader(myResponseStream, Encoding.UTF8);
      string retString = myStreamReader.ReadToEnd();
      myStreamReader.Close();
      myResponseStream.Close();
      Response.Write(retString);
    }

这个太复杂了 突然发现个简单的：

using (var client = new WebClient()){
  client.Encoding = Encoding.UTF8;
  string serviceAddress = urlappend + "cloud/device/data/getErrorData?appId=" + appid + "&accessToken=" + accessToken + "&timestamp=" + time + "&deviceIds=" + deviceIds;
   var data = client.DownloadString(serviceAddress);
   var obj = JsonConvert.DeserializeObject<JObject>(data);
}
//obj就是返回数据的对象

2.post方法调用接口获取json文件内容

public void PostFunction()
    {
      string serviceAddress = "http://222.111.999.444:8687/tttr/usercrd/uuu/12/dfd7e4";
      HttpWebRequest request = (HttpWebRequest)WebRequest.Create(serviceAddress);
      request.Method = "POST";
      request.ContentType = "application/json";
      string strContent = @"{ ""mmmm"": ""89e"",""nnnnnn"": ""0101943"",""kkkkkkk"": ""e8sodijf9""}";
      using (StreamWriter dataStream = new StreamWriter(request.GetRequestStream()))
      {
        dataStream.Write(strContent);
        dataStream.Close();
      }
      HttpWebResponse response = (HttpWebResponse)request.GetResponse();
      string encoding = response.ContentEncoding;
      if (encoding == null || encoding.Length < 1)
      {
        encoding = "UTF-8"; //默认编码 
      }
      StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.GetEncoding(encoding));
      string retString = reader.ReadToEnd();
      //解析josn
      JObject jo = JObject.Parse(retString);
      Response.Write(jo["message"]["mmmm"].ToString());
     
    } 

以上为个人经验，希望能给大家一个参考，也希望大家多多支持易采站长站。如有错误或未考虑完全的地方，望不吝赐教。