【C#】Get the html code of a webpage

As for the title,the console program will show you a sample which can get the webpage-code.Enjoy it:)

 using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 using System.Threading.Tasks;
 using System.Net;
 using System.IO;
 using System.Runtime.InteropServices; //dllimport relies on it
 namespace WebPageCode
 {

     class Program
     {

         [DllImport("kernel32.dll")]
         static extern uint GetTickCount();  

         static void addhead(ref string px) //add http head if necessary
         {
             if (px.Substring(, ).ToLower() != @"http://") px = @"http://" + px;
         }

         static string getwebcode(string PageUrl,string proxy=""){

             uint x = GetTickCount();

             addhead(ref PageUrl);  //webpage check
             WebClient wc = new WebClient();
             wc.Credentials = CredentialCache.DefaultCredentials; 

             proxy.Trim();  //proxy check
             if (proxy != "")
             {
                 addhead(ref proxy);
                 WebProxy wp = new WebProxy();
                 wp.Address = new Uri(proxy);
                 wc.Proxy = wp;
             }

             Byte[] pageData = wc.DownloadData(PageUrl);
             x = GetTickCount() - x; //x means the time spent.
             return Encoding.UTF8.GetString(pageData);

         }

         static void Main(string[] args)
         {
             int i = , n = args.Length;
             string proxy = "";
             string page = "";
             while (i < n)
             {
                 if (args[i] == "-proxy")
                 {
                     if (i<(n-)) proxy = args[++i];
                 }
                 if (args[i] == "-page")
                 {
                     if (i < (n - )) page = args[++i];
                 }
                 i++;
             }
             page.Trim(); proxy.Trim();
             if (page == "") return; //no webpage found
             string code;
             if (proxy == ""){
                 code=getwebcode(page);  //proxy found
             } else {
                 code=getwebcode(page,proxy);  //no proxy found
             }

             Console.Write(code);
             Console.ReadKey();
         }
     }
 }