c# 调用webapi的几种方式

 

HttpHelper帮助类

 public static class Httphelper
    {
        // Post请求
        public static string PostResponse(string url, string postData, out string statusCode)
        {
            string result = string.Empty;
            //设置Http的正文
            HttpContent httpContent = new StringContent(postData);
            //设置Http的内容标头
            httpContent.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("application/json");
            //设置Http的内容标头的字符
            httpContent.Headers.ContentType.CharSet = "utf-8";
            using (HttpClient httpClient = new HttpClient())
            {
                //异步Post
                HttpResponseMessage response = httpClient.PostAsync(url, httpContent).Result;
                //输出Http响应状态码
                statusCode = response.StatusCode.ToString();
                //确保Http响应成功
                if (response.IsSuccessStatusCode)
                {
                    //异步读取json
                    result = response.Content.ReadAsStringAsync().Result;
                }
            }
            return result;
        }

        // 泛型：Post请求
        public static T PostResponse<T>(string url, string postData) where T : class, new()
        {
            T result = default(T);

            HttpContent httpContent = new StringContent(postData);
            httpContent.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("application/json");
            httpContent.Headers.ContentType.CharSet = "utf-8";
            using (HttpClient httpClient = new HttpClient())
            {
                HttpResponseMessage response = httpClient.PostAsync(url, httpContent).Result;

                if (response.IsSuccessStatusCode)
                {
                    Task<string> t = response.Content.ReadAsStringAsync();
                    string s = t.Result;
                    //Newtonsoft.Json
                    string json = JsonConvert.DeserializeObject(s).ToString();
                    result = JsonConvert.DeserializeObject<T>(json);
                }
            }
            return result;
        }

        // 泛型：Get请求
        public static T GetResponse<T>(string url) where T : class, new()
        {
            T result = default(T);

            using (HttpClient httpClient = new HttpClient())
            {
                httpClient.DefaultRequestHeaders.Accept.Add(new System.Net.Http.Headers.MediaTypeWithQualityHeaderValue("application/json"));
                HttpResponseMessage response = httpClient.GetAsync(url).Result;

                if (response.IsSuccessStatusCode)
                {
                    Task<string> t = response.Content.ReadAsStringAsync();
                    string s = t.Result;
                    string json = JsonConvert.DeserializeObject(s).ToString();
                    result = JsonConvert.DeserializeObject<T>(json);
                }
            }
            return result;
        }

        // Get请求
        public static string GetResponse(string url, out string statusCode)
        {
            string result = string.Empty;

            using (HttpClient httpClient = new HttpClient())
            {
                httpClient.DefaultRequestHeaders.Accept.Add(new System.Net.Http.Headers.MediaTypeWithQualityHeaderValue("application/json"));

                HttpResponseMessage response = httpClient.GetAsync(url).Result;
                statusCode = response.StatusCode.ToString();

                if (response.IsSuccessStatusCode)
                {
                    result = response.Content.ReadAsStringAsync().Result;
                }
            }
            return result;
        }

        // Put请求
        public static string PutResponse(string url, string putData, out string statusCode)
        {
            string result = string.Empty;
            HttpContent httpContent = new StringContent(putData);
            httpContent.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("application/json");
            httpContent.Headers.ContentType.CharSet = "utf-8";
            using (HttpClient httpClient = new HttpClient())
            {
                HttpResponseMessage response = httpClient.PutAsync(url, httpContent).Result;
                statusCode = response.StatusCode.ToString();
                if (response.IsSuccessStatusCode)
                {
                    result = response.Content.ReadAsStringAsync().Result;
                }
            }
            return result;
        }

        // 泛型：Put请求
        public static T PutResponse<T>(string url, string putData) where T : class, new()
        {
            T result = default(T);
            HttpContent httpContent = new StringContent(putData);
            httpContent.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("application/json");
            httpContent.Headers.ContentType.CharSet = "utf-8";
            using (HttpClient httpClient = new HttpClient())
            {
                HttpResponseMessage response = httpClient.PutAsync(url, httpContent).Result;

                if (response.IsSuccessStatusCode)
                {
                    Task<string> t = response.Content.ReadAsStringAsync();
                    string s = t.Result;
                    string json = JsonConvert.DeserializeObject(s).ToString();
                    result = JsonConvert.DeserializeObject<T>(json);
                }
            }
            return result;
        }
    }

 

主要是Post传参的三种方式

  //方法一，传json参数
            var d = new {
                username = " ",
                password = " ",
                grant_type = "",
                appcode = " ",
                companyid = " ",
                version = "1.0",
            };
            var data = JsonConvert.SerializeObject(d);
            HttpContent httpContent = new StringContent(data);
            或
            var data=  "{\"username\":\"" + username+ "\",\"password\": \"" + password + "\",\"grant_type\": \"" + grant_type+ "\",\"version\": \"" + version+ "\"}";

 

 

//方法二，传表单参数
            FormUrlEncodedContent formContent = new FormUrlEncodedContent(new Dictionary<string, string>()
            {
                {"username"," " },
                {"password"," " },
                {"grant_type","" },
                {"appcode"," " },
                {"companyid"," " },
                {"version","1.0" },
             });

//方法三，传字节流   
 string postparas = @"{ ""username"":"" "",""password"":"" "",""grant_type"":"""",""appcode"":"" "",""companyid"":"" "",""version"":""1.0""}";
                using (Stream dataStream = new MemoryStream(Encoding.Unicode.GetBytes(postparas) ?? new byte[0]))
                {
                    using (HttpContent content = new StreamContent(dataStream))
                    {
                        
                    }
                }