对encodeURIComponent编码进行解码

using System; 
using System.Collections.Specialized; 
using System.Web; 
class Test 
{     
   static void Main()     
  {         
    Uri uri = new Uri("http://zhidao.baidu.com/q?word=win7+%B0%B2%D7%B0+%B0%B2%C8%AB&lm=0&fr=search&ct=17&pn=0&tn=ikaslist&rn=10");         
    string query = uri.Query;         
    NameValueCollection col = HttpUtility.ParseQueryString(query);         
    foreach (string key in col.AllKeys)        
     {             
      Console.WriteLine(key);            
      Console.WriteLine(col[key]);       
     }    
   } 
}