【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:)
 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Threading.Tasks;
 6 using System.Net;
 7 using System.IO;
 8 using System.Runtime.InteropServices; //dllimport relies on it
 9 namespace WebPageCode
10 {
11     
12     class Program
13     {
14         
15         [DllImport("kernel32.dll")]
16         static extern uint GetTickCount();  
17 
18         static void addhead(ref string px) //add http head if necessary
19         {
20             if (px.Substring(0, 7).ToLower() != @"http://") px = @"http://" + px;
21         }
22 
23         static string getwebcode(string PageUrl,string proxy=""){
24 
25             uint x = GetTickCount();
26 
27             addhead(ref PageUrl);  //webpage check
28             WebClient wc = new WebClient(); 
29             wc.Credentials = CredentialCache.DefaultCredentials; 
30             
31             proxy.Trim();  //proxy check
32             if (proxy != "")
33             {
34                 addhead(ref proxy);
35                 WebProxy wp = new WebProxy();
36                 wp.Address = new Uri(proxy);
37                 wc.Proxy = wp;
38             }
39 
40             Byte[] pageData = wc.DownloadData(PageUrl); 
41             x = GetTickCount() - x; //x means the time spent.
42             return Encoding.UTF8.GetString(pageData);
43 
44         }
45 
46         static void Main(string[] args)
47         {
48             int i = 0, n = args.Length;
49             string proxy = "";
50             string page = "";
51             while (i < n)
52             {
53                 if (args[i] == "-proxy")
54                 {
55                     if (i<(n-1)) proxy = args[++i];
56                 }
57                 if (args[i] == "-page")
58                 {
59                     if (i < (n - 1)) page = args[++i];
60                 }
61                 i++;
62             }
63             page.Trim(); proxy.Trim();
64             if (page == "") return; //no webpage found
65             string code;
66             if (proxy == ""){
67                 code=getwebcode(page);  //proxy found
68             } else {
69                 code=getwebcode(page,proxy);  //no proxy found
70             }
71             
72             Console.Write(code);
73             Console.ReadKey();
74         }
75     }
76 }