WinForms 的支持跨域的测试程序

using System;
using System.Diagnostics;
using System.IO;
using System.Net;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading;
using System.Windows.Forms;

namespace SimpleHttpServer_cors
{
   public partial class Form1 : Form
   {
       private HttpListener listener;
       private Thread listenerThread;
       private bool isStopping = false; // 标志位，用于指示服务是否正在停止


       public Form1()
       {
           InitializeComponent();
           this.FormClosing += Form1_FormClosing; // 订阅窗体关闭事件
           txtIPAddress.Text = GetLocalIP();
       }

       private void btnStartService_Click(object sender, EventArgs e)
       {
           string ipAddress = txtIPAddress.Text;
           string port = txtPort.Text;

           listener = new HttpListener();
           listener.Prefixes.Add($"http://{ipAddress}:{port}/");

           listenerThread = new Thread(StartListener);
           listenerThread.Start();

           MessageBox.Show("服务已启动");
       }

       private void StartListener()
       {
           listener.Start();
           while (listener.IsListening)
           {
               try
               {
                   var context = listener.GetContext();
                   ThreadPool.QueueUserWorkItem(o => HandleRequest(context));
               }
               catch (HttpListenerException)
               {
                   // 监听器已停止
                   break;
               }
           }
       }

       private void HandleRequest(HttpListenerContext context)
       {
           string responseString = string.Empty;

           if (context.Request.HttpMethod == "GET" && context.Request.Url.AbsolutePath == "/getapi/getadate/test2")
           {
               responseString = "{\"sites\":[{\"name\":\"菜鸟教程\",\"get_url\":\"www.runoob.com\"},{\"name\":\"google\",\"get_url\":\"www.google.com\"},{\"name\":\"微博\",\"get_url\":\"www.weibo.com\"}]}";
           }
           else if (context.Request.HttpMethod == "POST" && context.Request.Url.AbsolutePath == "/postapi/test1")
           {
               using (var reader = new StreamReader(context.Request.InputStream, context.Request.ContentEncoding))
               {
                   string requestData = reader.ReadToEnd();
                   Console.WriteLine($"Received POST data: {requestData}");
               }
               responseString = "{\"sites\":[{\"name\":\"菜鸟教程\",\"post_url\":\"www.runoob.com\"},{\"name\":\"google\",\"post_url\":\"www.google.com\"},{\"name\":\"微博\",\"post_url\":\"www.weibo.com\"}]}";
           }

           //跨域的
           context.Response.Headers.Add("Access-Control-Allow-Origin", "*");
           context.Response.Headers.Add("Access-Control-Allow-Methods", "GET, POST, OPTIONS");
           context.Response.Headers.Add("Access-Control-Allow-Headers", "Content-Type");

           byte[] buffer = Encoding.UTF8.GetBytes(responseString);
           context.Response.ContentLength64 = buffer.Length;

           context.Response.OutputStream.Write(buffer, 0, buffer.Length);
           context.Response.OutputStream.Close();
       }

       private void btnStopService_Click(object sender, EventArgs e)
       {
           StopService();
       }

       private void StopService()
       {
           if (listener != null && listener.IsListening)
           {
               isStopping = true;
               listener.Stop();
               listener.Close();

               listenerThread.Join();

               MessageBox.Show("服务已暂停");
           }
       }

       private void Form1_FormClosing(object sender, FormClosingEventArgs e)
       {
           StopService(); // 确保在窗体关闭时停止服务
       }

       /// <summary>
       /// 获取当前使用的IP
       /// </summary>
       /// <returns></returns>
       public string GetLocalIP()
       {
           string result = RunApp("route", "print", true);
           Match m = Regex.Match(result, @"0.0.0.0\s+0.0.0.0\s+(\d+.\d+.\d+.\d+)\s+(\d+.\d+.\d+.\d+)");
           if (m.Success)
           {
               return m.Groups[2].Value;
           }
           else
           {
               try
               {
                   System.Net.Sockets.TcpClient c = new System.Net.Sockets.TcpClient();
                   c.Connect("www.baidu.com", 80);
                   string ip = ((System.Net.IPEndPoint)c.Client.LocalEndPoint).Address.ToString();
                   c.Close();
                   return ip;
               }
               catch (Exception)
               {
                   return null;
               }
           }
       }

       /// <summary>
       /// 运行一个控制台程序并返回其输出参数。
       /// </summary>
       /// <param name="filename">程序名</param>
       /// <param name="arguments">输入参数</param>
       /// <returns></returns>
       public string RunApp(string filename, string arguments, bool recordLog)
       {
           try
           {
               if (recordLog)
               {
                   Trace.WriteLine(filename + " " + arguments);
               }
               Process proc = new Process();
               proc.StartInfo.FileName = filename;
               proc.StartInfo.CreateNoWindow = true;
               proc.StartInfo.Arguments = arguments;
               proc.StartInfo.RedirectStandardOutput = true;
               proc.StartInfo.UseShellExecute = false;
               proc.Start();

               using (System.IO.StreamReader sr = new System.IO.StreamReader(proc.StandardOutput.BaseStream, Encoding.Default))
               {
                   Thread.Sleep(100);           //貌似调用系统的nslookup还未返回数据或者数据未编码完成，程序就已经跳过直接执行
                                                //txt = sr.ReadToEnd()了，导致返回的数据为空，故睡眠令硬件反应
                   if (!proc.HasExited)         //在无参数调用nslookup后，可以继续输入命令继续操作，如果进程未停止就直接执行
                   {                            //txt = sr.ReadToEnd()程序就在等待输入，而且又无法输入，直接掐住无法继续运行
                       proc.Kill();
                   }
                   string txt = sr.ReadToEnd();
                   sr.Close();
                   if (recordLog)
                       Trace.WriteLine(txt);
                   return txt;
               }
           }
           catch (Exception ex)
           {
               Trace.WriteLine(ex);
               return ex.Message;
           }
       }
   }
}

需要在防火墙的规则中添加对应的端口：

在另外一个电脑中访问：

1：启动服务
2：展示一下另外一个电脑的IP地址
3：在浏览器中进行请求
4：请求完成显示信息

使用的html文件源码
需要修改代码中的IP地址：localhost 修改为服务器的IP地址。

<!DOCTYPE html>
<html>
<head>
    <title>CORS Test</title>
</head>
<body>
    <button onclick="fetchData()">Fetch Data</button>
    <div id="result"></div>

    <script>
        function fetchData() {
            fetch('http://localhost:18792/getapi/getadate/test2')
                .then(response => response.json())
                .then(data => {
                    document.getElementById('result').innerText = JSON.stringify(data, null, 2);
                })
                .catch(error => console.error('Error:', error));
        }
    </script>
</body>
</html>