C# 没有来自 GET 请求的值

Question

我在 C# 中有一个 WinForms 应用程序，我试图通过带有 HTTPS 协议的 GET 请求获取页面的 HTML 代码，但我无法获得任何值。

我尝试了多种解决方案，但我无法自行解决此问题。

代码如下：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Net;
using System.Net.Http;
using System.IO;

namespace sharpFUT
{
    public partial class frmShapfut : Form
    {
        string HTMLCode;

        public frmShapfut()
        {
            InitializeComponent();
        }

        private async void btnSearch_Click(object sender, EventArgs e)
        {
            try
            {
                HTMLCode = await getHTMLCode(tbxPlayerURL.Text);
            }
            catch (Exception)
            {
                MessageBox.Show(e.ToString());
            }

            MessageBox.Show(HTMLCode);
        }

        private async Task<string> getHTMLCode(string url)
        {
            var handler = new HttpClientHandler()
            {
                AllowAutoRedirect = true
            };

            
            HttpClient httpClient = new HttpClient(handler);

            httpClient.DefaultRequestHeaders.Add("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.124 Safari/537.36");
            httpClient.DefaultRequestHeaders.Add("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9");

            var result = await httpClient.GetStringAsync(url);

            return result;
        }
    }
}