使用HttpWebRequest向webapi傳遞數據並接收

1.通過路由接收參數，一般直接通過Url拼接直接匹配路由對應參數

這個直接通過設置路由，然后Url的位置對應即可；

 

2.通過QueryString傳遞參數

一般常見於Get訪問數據傳參；

 

3.通過[FromBody]直接在形參接收數據

客戶端代碼：

private async void Btn_SendData_Click(object sender, EventArgs e)
        {
            if (string.IsNullOrEmpty(TB_SendDataUrl.Text))
                return;
            HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(TB_SendDataUrl.Text);
            //request.ContentType = "application/x-www-form-urlencoded";//post發送數據必須使用這個標頭才能被webapi [frombody]接收
            request.ContentType = "application/json";   //如果用了newtonsoft json 轉換數據，那么必須用此標頭，否則服務器將無法解析數據
            request.Method = "post";

            //發送的數據
            List<Person> listP = new List<Person>();
            Person p1 = new Person { ID = 1, Name = "張三", Age = 27 };
            Person p2 = new Person { ID = 2, Name = "李四", Age = 25 };
            Person p3 = new Person { ID = 3, Name = "王五", Age = 28 };
            listP.Add(p1); listP.Add(p2); listP.Add(p3);


            byte[] byteArray;
            Person p = new Person { ID = 1, Name = "張三", Age = 27 };
            //byteArray = Encoding.UTF8.GetBytes(ParseToString(p));
            string data = await JsonConvert.SerializeObjectAsync(listP);//直接序列化比上一行代碼 更方便
            byteArray = Encoding.UTF8.GetBytes(data);//對數據進行轉碼，可以將中文數據進行傳輸
            request.ContentLength = byteArray.Length;

            Stream reqStream = await request.GetRequestStreamAsync();
            reqStream.Write(byteArray,0,byteArray.Length);
            reqStream.Close();

            string responseFromServer = string.Empty;
            WebResponse response = await request.GetResponseAsync();
            using (StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.UTF8))
            {
                responseFromServer = reader.ReadToEnd();
            }
            if(string.IsNullOrEmpty(responseFromServer))
            {
                TB_SendResponseData.Text = "NULL";
            }
            else
            {
                TB_SendResponseData.Text = responseFromServer;
                List<Person> resData = JsonConvert.DeserializeObject<List<Person>>(responseFromServer);
                
            }
            response.Close();
        }

這里注意如果使用Newtonsoft將傳輸數據轉換成了json，需要將contenttype設置為"application/json"，這里十分關鍵，如果不是這個表頭，服務端將不能正確解析數據

服務端代碼：

   [HttpPost]
        public List<Person> SendListData([FromBody] List<Person> listP)
        {

            return listP;
        }

 

 

4.通過 解析Request.Content  中的請求消息實體得到數據，這種一般是通過Post上傳的數據

 [HttpPost]
        public async Task<List<Person>> SendListJsontData()
        {
            List<Person> data = await this.Request.Content.ReadAsAsync<List<Person>>();
            return data;
        }

由於Task是4.5以上框架引入的，也可以在4.5以下框架中寫成非異步調用的方式：

[HttpPost]
        public string PostNewData()
        {
            var t = this.Request.Content.ReadAsStringAsync();
            string data = t.Result;
            return data;
        }

前台使用的代碼(推薦)：

public static string HttpPost(string url, string PostData)
        {
            Encoding encoding = Encoding.UTF8;
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
            request.Method = "POST";
            request.Accept = "text/html, application/xhtml+xml, */*";
            //這里只有使用var data = HttpContext.Current.Request.Form["Name"].ToString();才切換到表單
            //如果api使用Request.Content.ReadAsStringAsync();則無所謂切換
            request.ContentType = "application/x-www-form-urlencoded ";//根據服務端進行 切換
            //request.ContentType = "application/json; charset=utf-8 ";

            byte[] buffer = encoding.GetBytes(PostData);
            request.ContentLength = buffer.Length;
            request.GetRequestStream().Write(buffer, 0, buffer.Length);
            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            using (StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.UTF8))
            {
                return reader.ReadToEnd();
            }
        }

主函數調用

static void Main(string[] args)
        {
　　　　　　　string url = "http://localhost:50041/api/Home/PostNewData";
            //string data = "Name=";
            //for (int i = 0; i < 1000; i++)
            //{
            //    data += Guid.NewGuid().ToString() + ";";
            //}

            string data = "Id=9527&Name=zhangSan&Category=A8&Price=88";

            string res = HttpPost(url, data);

            Console.WriteLine($"結果：{res}");
            Console.ReadKey();
        }

 

使用.Net內置的方法即可讀到傳輸數據。