试图发送HTTP请求时奇怪的例外

Question

我在尝试通过执行HTTP请求来获取网站内容的同时获得此例外。 我尝试了几个不同的URL（包括粘贴），并且我得到了一个奇怪的例外，这些例外是我从未得到过的：

    private static string GetWebsiteContent()
    {
        
        try
        {
            var webClient = new WebClient();
            webClient.Headers.Add("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:96.0) Gecko/20100101 Firefox/96.0");

            Console.WriteLine(webClient.DownloadString("https://pastebin.com/MyUrl"));
           

            return null;
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.ToString());
        }

        return null;
    }

这是我所说的方法，我不需要任何形式的解释，只是对网站的简单请求。

例外：

System.Configuration.ConfigurationErrorsException: Impossibile inizializzare il sistema di configurazione ---> System.Configuration.ConfigurationErrorsException: Errore durante il cari
camento di un file di configurazione: L'inizializzatore di tipo di 'System.MarvinHash' ha generato un'eccezione. (C:\Windows\Microsoft.NET\Framework64\v4.0.30319\Config\machine.config)
 ---> System.TypeInitializationException: L'inizializzatore di tipo di 'System.MarvinHash' ha generato un'eccezione. ---> System.NullReferenceException: Riferimento a un oggetto non im
postato su un'istanza di oggetto.
   in System.Collections.HashHelpers.GetEntropy()
   in System.OrdinalComparer.System.IWellKnownStringEqualityComparer.GetRandomizedEqualityComparer()
   in System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value, Boolean add)
   in System.Security.Cryptography.CryptoConfig.get_DefaultNameHT()
   in System.Security.Cryptography.CryptoConfig.CreateFromName(String name, Object[] args)
   in System.Security.Cryptography.RandomNumberGenerator.Create()
   in System.MarvinHash.GenerateSeed()
   in System.MarvinHash..cctor()
   --- Fine della traccia dello stack dell'eccezione interna ---
   in System.Xml.NameTable..ctor()
   in System.Configuration.XmlUtil..ctor(Stream stream, String name, Boolean readToFirstElement, ConfigurationSchemaErrors schemaErrors)
   in System.Configuration.BaseConfigurationRecord.InitConfigFromFile()
   --- Fine della traccia dello stack dell'eccezione interna ---
   in System.Configuration.ConfigurationSchemaErrors.ThrowIfErrors(Boolean ignoreLocal)
   in System.Configuration.BaseConfigurationRecord.ThrowIfParseErrors(ConfigurationSchemaErrors schemaErrors)
   in System.Configuration.ClientConfigurationSystem.EnsureInit(String configKey)
   --- Fine della traccia dello stack dell'eccezione interna ---
   in System.Configuration.ClientConfigurationSystem.EnsureInit(String configKey)
   in System.Configuration.ClientConfigurationSystem.PrepareClientConfigSystem(String sectionName)
   in System.Configuration.ClientConfigurationSystem.System.Configuration.Internal.IInternalConfigSystem.GetSection(String sectionName)
   in System.Configuration.ConfigurationManager.GetSection(String sectionName)
   in System.Configuration.PrivilegedConfigurationManager.GetSection(String sectionName)
   in System.Diagnostics.DiagnosticsConfiguration.GetConfigSection()
   in System.Diagnostics.DiagnosticsConfiguration.Initialize()
   in System.Diagnostics.DiagnosticsConfiguration.get_Sources()
   in System.Diagnostics.TraceSource.Initialize()
   in System.Net.Logging.InitializeLogging()
   in System.Net.Logging.get_On()
   in System.Net.WebClient.DownloadString(Uri address)
   in SchoolProject.WebUtils.GetWebsiteContent() in C:\Users\Admin\Desktop\Projects\CS\SchoolProject\WebUtils.cs:riga 25

Process finished with exit code -1,073,741,510.

IM在不同的计算机上尝试了以下代码，但结果仍然相同。

我正在使用.NET 4.0（必须）

有人知道为什么会发生这种情况以及如何解决此问题？

Answer 1

不再建议使用WebClient。最好使用httpclient而不是

private static async Task<string> GetWebsiteContent()
{
    try
    {
         var client = new HttpClient();
         //If You Need Add Header 
         //client.DefaultRequestHeaders.TryAddWithoutValidation("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:96.0) Gecko/20100101 Firefox/96.0");       
         var response = await client.GetAsync("https://pastebin.com/url");
         var content = await response.Content.ReadAsStringAsync();
         return content;
     }
     catch (Exception ex)
     {
          Console.WriteLine(ex.ToString());
     }

        return null;
  }