Httpt请求

在c#中常见发送http请求的方式如下

• HttpWebRequest：

.net 平台原生提供，这是.NET创建者最初开发用于使用HTTP请求的标准类。使用HttpWebRequest可以让开发者控制请求/响应流程的各个方面，如 timeouts, cookies, headers, protocols。
关于使用HttpWebRequest上传和下载文件，可参考：《c#使用Http上传下载文件》：https://blog.csdn.net/u010476739/article/details/105074171

• WebClient：

.net 平台原生提供，WebClient是一种更高级别的抽象，是HttpWebRequest为了简化最常见任务而创建的，但也因此缺少了HttpWebRequest的灵活性。

• HttpClient：

.net 平台原生提供，.net core 推荐使用HttpClient  ：https://blog.csdn.net/u010476739/article/details/119782562

HttpWebRequest 使用

1.获取token接口

 1 private string gettoken()
 2         {
 3             // 测试环境登陆用户
 4             //string username = "as";
 5             //string password = "as";
 6
 7             string Token = string.Empty;
 8             try
 9             {
10                 if (string.IsNullOrEmpty(username) && username == null && string.IsNullOrEmpty(password) && password == null)
11                     throw new Exception("调用系统接口：获取token失败 用户名或密码不能发为空！");
12                 var strParm = JsonConvert.SerializeObject(new
13                 {
14                     username = username,
15                     password = password
16                 });
17                 //string url = "http接口地址";    // 测试系统地址
18
19                 Encoding encode = System.Text.Encoding.Default;
20                 Byte[] arrB = encode.GetBytes(strParm);
21                 HttpWebRequest Request = (HttpWebRequest)HttpWebRequest.Create(url);
22                 Request.Method = "POST";
23                 Request.ContentType = "application/json";  // application/x-www-form-urlencoded
24
25                 Request.ContentLength = arrB.Length;
26                 //实例化写入请求的参数
27                 using (Stream outStream = Request.GetRequestStream())
28                 {
29                     outStream.Write(arrB, 0, arrB.Length);
30                     outStream.Close();
31                 }
32
33                 //接受http响应
34                 HttpWebResponse myResponse = Request.GetResponse() as HttpWebResponse;
35                 //读取http返回的数据流
36                 Stream ReceiveStream = myResponse.GetResponseStream();
37
38                 using (StreamReader reader = new StreamReader(ReceiveStream, Encoding.UTF8))
39                 {
40                     Token = reader.ReadToEnd();
41                     reader.Close();
42                 }
43                 myResponse.Close();
44
45                 JObject obj = JObject.Parse(Token);
46
47                 var msg = obj.GetValue("msg").ToString();
48                 if (msg != "操作成功")
49                     throw new Exception(msg);
50
51                 Token = obj.GetValue("token").ToString();
52             }
53             catch (Exception ex)
54             {
55                 throw ex;
56             }
57             return Token;
58         }

2.获取信息接口+表头token串

 1 private string GetbjMerial(JObject infostr)
 2         {
 3             var apiResult = new ResultMessage();
 4             string result = string.Empty;
 5             try
 6             {
 7                 string url = "http接口地址";    // 测试系统地址
 8
 9                 var para = JsonConvert.SerializeObject(infostr);
10
11                 Encoding encode = System.Text.Encoding.Default;
12                 Byte[] arrB = encode.GetBytes(para);
13
14                 //获取token
15                 string token = this.gettoken();
16
17                 HttpWebRequest Request = HttpWebRequest.Create(url) as HttpWebRequest;
18                 Request.Method = "POST";
19                 Request.ContentType = "text/plain";  //"application/json";
20                 Request.Headers.Add("Authorization", token);
21                 Request.ContentLength = arrB.Length;
22                 //实例化写入请求的参数
23                 using (Stream outStream = Request.GetRequestStream())
24                 {
25                     outStream.Write(arrB, 0, arrB.Length);
26                     outStream.Close();
27                 }
28
29                 //接受http响应
30                 HttpWebResponse myResponse = Request.GetResponse() as HttpWebResponse;
31                 //读取http返回的数据流
32                 Stream ReceiveStream = myResponse.GetResponseStream();
33
34                 using (StreamReader reader = new StreamReader(ReceiveStream, Encoding.UTF8))
35                 {
36                     result = reader.ReadToEnd();
37                     reader.Close();
38                 }
39                 myResponse.Close();
40
41             }
42             catch (Exception ex)
43             {
44                 throw ex;
45             }
46             return result;
47         }

2.1.获取token

public string gettoken()
{

            string Token = string.Empty;
            try
            {
                //入参
                var par = new { a= db, b = login, password = password };
                var strParm = JsonConvert.SerializeObject(new
                {
                    @params = par
                });
                string url = “”；

                Encoding encode = System.Text.Encoding.Default;
                Byte[] arrB = encode.GetBytes(strParm);
                HttpWebRequest Request = (HttpWebRequest)HttpWebRequest.Create(url);
                Request.Method = "POST";
                Request.CookieContainer = new System.Net.CookieContainer();
                Request.ContentType = "application/json";  // application/x-www-form-urlencoded

                Request.ContentLength = arrB.Length;
                //实例化写入请求的参数
                using (Stream outStream = Request.GetRequestStream())
                {
                    outStream.Write(arrB, 0, arrB.Length);
                    outStream.Close();
                }

                //接受http响应
                HttpWebResponse myResponse = Request.GetResponse() as HttpWebResponse;
                //读取http返回的数据流
                Stream ReceiveStream = myResponse.GetResponseStream();

                string mes = "";

                using (StreamReader reader = new StreamReader(ReceiveStream, Encoding.UTF8))
                {
                    mes = reader.ReadToEnd();
                    reader.Close();
                }
                myResponse.Close();

                JObject obj = JObject.Parse(mes);
                //dynamic resa = JsonConvert.DeserializeObject(mes);

                if (obj.Property("result") != null)  // 存在结果集
                {
                    JObject res= obj.GetValue("result").ToObject<JObject>();
                    if(res.GetValue("username").ToString() == login && res.GetValue("name").ToString() == login)
                    {
                        // 调用成功，获取token
                        System.Net.HttpWebResponse response = (System.Net.HttpWebResponse)Request.GetResponse();

                        var json = Newtonsoft.Json.JsonConvert.SerializeObject(response.Cookies);

                        if (response.Cookies.Count > 0)
                        {
                            Token = response.Cookies[0].Name + "=" + response.Cookies[0].Value;
                        }
                    }
                }
                if(obj.Property("error") != null)    // 失败
                {
                    JObject res = obj.GetValue("error").ToObject<JObject>();
                    JObject resdata = res.GetValue("data").ToObject<JObject>();

                    throw new Exception("调用接口失败，错误信息："+ res.GetValue("message").ToString() + " "+ resdata.GetValue("message").ToString());
                }

            }
            catch (Exception ex)
            {
                throw ex;
            }
            return Token;
        }

通过返回接口的cookie中获取session_id作为获取数据接口的request请求的cookie调用接口。

2.2.根据2.1接口返回token结果获取数据

public dynamic GetData(string para)
        {
            var apiResult = new ResultMessage();
            dynamic data ;
            try
            {
                string url ="";

                Encoding encode = System.Text.Encoding.Default;
                Byte[] arrB = encode.GetBytes(para);

                //获取token
                string token = this.gettoken();
                HttpWebRequest Request = HttpWebRequest.Create(url) as HttpWebRequest;
                Request.Method = "POST";
                Request.ContentType = "application/json";
                Request.Headers.Add("Cookie", token);
                Request.ContentLength = arrB.Length;
                //实例化写入请求的参数
                using (Stream outStream = Request.GetRequestStream())
                {
                    outStream.Write(arrB, 0, arrB.Length);
                    outStream.Close();
                }

                //接受http响应
                HttpWebResponse myResponse = Request.GetResponse() as HttpWebResponse;
                //读取http返回的数据流
                Stream ReceiveStream = myResponse.GetResponseStream();

                string str = string.Empty;
                using (StreamReader reader = new StreamReader(ReceiveStream, Encoding.UTF8))
                {
                    str = reader.ReadToEnd();
                    reader.Close();
                }
                myResponse.Close();

                dynamic res = JsonConvert.DeserializeObject(str);
                dynamic result = JsonConvert.DeserializeObject(Convert.ToString(res.result));

                if(Convert.ToString(result.code) =="200" && Convert.ToString(result.msg) == "操作成功")
                {
                    data = JsonConvert.DeserializeObject(Convert.ToString(result.data));
                }
                else
                {
                    throw new Exception("接口失败，错误代码：" + Convert.ToString(result.code) + ",错误信息:" +Convert.ToString(result.msg));
                }

            }
            catch (Exception ex)
            {
                throw ex;
            }
            return data;
        }

其他方式可访问：http://t.zoukankan.com/damugua-p-14368067.html

部分内容参考：https://blog.csdn.net/u010476739/article/details/119782562