hashtable and dictionary

      

using System;
using System.Collections.Generic;

using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Collections;

namespace WindowsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            listBox1.Items.Clear();
            listBox2.Items.Clear();
            //using System.Collections;
            Hashtable ht = new Hashtable();
            ht.Add("001",1);
            ht.Add("002",2);
            ht.Add("003",3);

            foreach (string str in ht.Keys)
            {
                listBox2.Items.Add(ht[str]);
            }
            foreach(DictionaryEntry h in ht)
            {
                listBox1.Items.Add(h.Key);
            }
           

        }

        private void button2_Click(object sender, EventArgs e)
        {
            listBox2.Items.Clear();
            listBox1.Items.Clear();
            //using System.Collections.Generic;
            Dictionary<string, double> dictionary = new Dictionary<string, double>();
            dictionary.Add("001", 1);
            dictionary.Add("002", 2);
            dictionary.Add("003", 3);
            foreach (string str in dictionary.Keys)
            {
                listBox2.Items.Add(dictionary[str]);
            }
            foreach(KeyValuePair<string ,double> kvp in dictionary)
            {
                listBox1.Items.Add(kvp.Key);
            }
        }
    }
}