.net 4.6环境下
.net4.6支持异步编程
命名空间：
using System;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;创建一个异步方法发送请求：
public static async Task<string> CallWebAPIAsync(string url, string method, string data)
{using (var client = new HttpClient()){HttpResponseMessage response;if (method.ToUpper() == "GET"){// 如果是GET请求response = await client.GetAsync(url);}else if (method.ToUpper() == "POST"){// 如果是POST请求var content = new StringContent(data, Encoding.UTF8, "application/json");response = await client.PostAsync(url, content);}else{throw new InvalidOperationException("Unsupported method: " + method);}// 确保HTTP请求成功response.EnsureSuccessStatusCode();// 读取并返回响应内容return await response.Content.ReadAsStringAsync();}
}调用这个方法：
private async void button1_Click(object sender, EventArgs e){try{string data = "{\"id\":\"\",\"properties\":\"\"}";string url = "";string method="POST";//GETstring result = await callWebApiAsync(url,method, data);richTextBox1.Text = result;}catch (Exception ex){Console.WriteLine("发生错误: " + ex.Message);}}一定要保证，调用时调用的方法满足异步操作。方法应该标记为async 并返回Task。
如果还有其他需求，比如返回的是一个标准的json格式字符串，那我们可以进行加工，转化为我们需要的json格式数据。
这里需要添加引用“Newtonsoft.Json”
首先找到返回的字符串的json格式，我们一般使用json.cn进行转化，选择“json转c#实体”
将返回结果复制进去即可得到json格式，将格式复制在代码中，例如
public class ResultItem{/// <summary>/// 姓名/// </summary>public string name{ get; set; }}public class Root{/// <summary>/// /// </summary>public List<ResultItem> result { get; set; }/// <summary>/// /// </summary>public string success { get; set; }/// <summary>/// /// </summary>public string errorMsg { get; set; }}然后进行转化：
try{string data = "{\"id\":\"\",\"properties\":{ \name\": \"\"}}";string url = "";string method="POST";//GETstring result = await callWebApiAsync(url,method, data);var v = JsonConvert.DeserializeObject<Root>(result);v.result.ForEach(x => {if (x.name.StartsWith("name******")) {richTextBox1.Text += x.name+"\n";}});}catch (Exception ex){Console.WriteLine("发生错误: " + ex.Message);}.net 4.0环境下
.net4.0没有原生的async、 await
.net不支持HttpClient
通常会使用webclient、httpwebrequest来进行HTTP请求。
命名空间：
using Newtonsoft.Json;
using System.Net;
using System.IO;http请求：
private static string PostHTTP(string url, string data){var request = (HttpWebRequest)WebRequest.Create(url);request.Method = "POST";request.ContentType = "application/json";using (var streamWriter = new StreamWriter(request.GetRequestStream())){streamWriter.Write(data);}using (var response = (HttpWebResponse)request.GetResponse()){using (var reader = new StreamReader(response.GetResponseStream())){return reader.ReadToEnd();}}}调用方法：
private void get(){try{string url = "";string data = "{\"id\":\"\",\"properties\":{ \"name\": \"\"}}";string result = PostHTTP(url, data);var v = JsonConvert.DeserializeObject<Root>(result);v.result.ForEach(x => {if (x.bl_item_item_id.StartsWith("5001*****")){richTextBox1.Text += x.name + "\n";}});}catch (Exception ex){MessageBox.Show(ex.Message, "出错", MessageBoxButtons.OK, MessageBoxIcon.Error);}}public class ResultItem{/// <summary>/// 姓名/// </summary>public string name { get; set; }}public class Root{/// <summary>/// /// </summary>public List<ResultItem> result { get; set; }/// <summary>/// /// </summary>public string success { get; set; }/// <summary>/// /// </summary>public string errorMsg { get; set; }}
