WikiHello.cs

using System;
using System.Net;
using System.Text.RegularExpressions;

namespace WikiHello
{
    class WikiHello
    {
        static void Main(string[] args)
        {
            Console.WriteLine();
            Console.Write("[");
            string s = new WebClient().DownloadString(
                "https://test.wikipedia.org/w/api.php?" +
                "action=query&format=xml&prop=revisions&titles=User%3AVort%2FHello&rvprop=content");
            Console.Write(Regex.Match(s, "e\">([^<]+)</r").Groups[1].Value);
            Console.WriteLine("]");
        }
    }
}