using System;
using System.Collections;
 
namespace HashtableExample
{
  class Program
  {
    static Hashtable hashtable = new Hashtable();
    static void Main(string[] args)
    {
      hashtable.Add("first", "Beijing");
      hashtable.Add("second", "Shanghai");
      hashtable.Add("third", "Hangzhou");
      hashtable.Add("forth", "Nanjing");
 
      //遍历方法一：遍历哈希表中的键
      foreach (string key in hashtable.Keys)
      {
        Console.WriteLine(hashtable[key]);
      }
      Console.WriteLine("--------------------");
 
      //遍历方法二：遍历哈希表中的值
      foreach(string value in hashtable.Values)
      {
        Console.WriteLine(value);
      }
      Console.WriteLine("--------------------");
 
      //遍历方法三：遍历哈希表中的键值
      foreach (DictionaryEntry de in hashtable)
      {
        Console.WriteLine(de.Value);
      }
      Console.WriteLine("--------------------");
 
      //遍历方法四：遍历哈希表中的键值
      IDictionaryEnumerator myEnumerator = hashtable.GetEnumerator();
      while (myEnumerator.MoveNext())
      {
        Console.WriteLine(hashtable[myEnumerator.Key]);
      }
    }
  }
}