Hashtable ht1 = new Hashtable(); //创建一个Hashtable实例
            ht1.Add("张三", "100"); //添加keyvalue键值对
            ht1.Add("李四", "100");
            ht1.Add("王五", "100");
            ht1.Add("赵六", "200");
            string capital1 = (string)ht["王五"];//根据Key值获取信息
            ht.Remove("赵六"); //移除一个keyvalue键值对 ht.Clear(); //移除所有元素
            object value2 = ht["赵六"];//直接根据key取值，判断类型在进行转化
            if (value2 is string)
            {

            }
            foreach (DictionaryEntry de in ht) //ht为一个Hashtable实例,遍历哈希表 object对象
            {
                Control cc = (Control)de.Value;  
            }
            //添加数据时Hashtable快。频繁调用数据时Dictionary快。

Stopwatch sw = new Stopwatch();
Hashtable hashtable = new Hashtable();
Dictionary<string, int> dictionary = new Dictionary<string, int>();
int countNum = 1000000;

sw.Start();
for (int i = 0; i < countNum; i++)
{
    hashtable.Add(i.ToString(), i);
}
sw.Stop();
Console.WriteLine(sw.ElapsedMilliseconds);  //输出: 744

sw.Restart();
for (int i = 0; i < countNum; i++)
{
    dictionary.Add(i.ToString(), i);
}
sw.Stop();
Console.WriteLine(sw.ElapsedMilliseconds);  //输出: 489

sw.Restart();
for (int i = 0; i < countNum; i++)
{
    hashtable.ContainsKey(i.ToString());
}
sw.Stop();
Console.WriteLine(sw.ElapsedMilliseconds);  //输出: 245

sw.Restart();
for (int i = 0; i < countNum; i++)
{
    dictionary.ContainsKey(i.ToString());
}
sw.Stop();
Console.WriteLine(sw.ElapsedMilliseconds);  //输出: 192