C#中遍历Hashtable的4种方法

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]);
       }
     }
   }
}