Obter mensagem de erro em Post HttpClient

CSharp · Console

/Program.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Xml;
public class Program
{
	public static void Main()
	{
		 string html = @"<?xml version=""1.0"" encoding=""utf-8""?>
<!DOCTYPE html PUBLIC ""-//W3C//DTD XHTML 1.0 Transitional//EN"" ""http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"">
<html xmlns=""http://www.w3.org/1999/xhtml"">
  <head>
    <title>Request Error</title>
    <style>BODY { color: #000000; background-color: white; font-family: Verdana; margin-left: 0px; margin-top: 0px; } #content { margin-left: 30px; font-size: .70em; padding-bottom: 2em; } A:link { color: #336699; font-weight: bold; text-decoration: underline; } A:visited { color: #6699cc; font-weight: bold; text-decoration: underline; } A:active { color: #336699; font-weight: bold; text-decoration: underline; } .heading1 { background-color: #003366; border-bottom: #336699 6px solid; color: #ffffff; font-family: Tahoma; font-size: 26px; font-weight: normal;margin: 0em 0em 10px -20px; padding-bottom: 8px; padding-left: 30px;padding-top: 16px;} pre { font-size:small; background-color: #e5e5cc; padding: 5px; font-family: Courier New; margin-top: 0px; border: 1px #f0f0e0 solid; white-space: pre-wrap; white-space: -pre-wrap; word-wrap: break-word; } table { border-collapse: collapse; border-spacing: 0px; font-family: Verdana;} table th { border-right: 2px white solid; border-bottom: 2px white solid; font-weight: bold; background-color: #cecf9c;} table td { border-right: 2px white solid; border-bottom: 2px white solid; background-color: #e5e5cc;}</style>
  </head>
  <body>
    <div id=""content"">
      <p class=""heading1"">Request Error</p>
      <p>The server encountered an error processing the request. The exception message is 'A base de dados Teste não pertence a empresa Alfalagos.'. See server logs for more details. The exception stack trace is: </p>
      <p>   at Custom.OuroNet.Server.WCFCadastre.Cadastro.DoWork(DTOMessageRequest messageRequest)
   at SyncInvokeDoWork(Object , Object[] , Object[] )
   at System.ServiceModel.Dispatcher.SyncMethodInvoker.Invoke(Object instance, Object[] inputs, Object[]& outputs)
   at System.ServiceModel.Dispatcher.DispatchOperationRuntime.InvokeBegin(MessageRpc& rpc)
   at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage5(MessageRpc& rpc)
   at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage31(MessageRpc& rpc)
   at System.ServiceModel.Dispatcher.MessageRpc.Process(Boolean isOperationContextSet)</p>
    </div>
  </body>
</html>";
            HtmlAgilityPack.HtmlDocument document = new HtmlAgilityPack.HtmlDocument();
            document.LoadHtml(html);
            HtmlAgilityPack.HtmlNode node = document.DocumentNode;
            HtmlAgilityPack.HtmlNode content = node.Descendants("div").
           Where(div => div.GetAttributeValue("id", string.Empty) == "content").
           FirstOrDefault();
            if(content!=null)
            {
                Console.WriteLine(content.InnerText);
            }
	}
}