关于C# 堆栈 Stack

using System.Collections;

       static void Main(string[] args)
        {
            TestStack();
        }

        //------------------------------------------------------
        // 堆栈（Stack）

        public static void TestStack()
        {
            Stack st = new Stack();

            st.Push('a');
            st.Push('b');
            st.Push('c');
            st.Push('d');

            Console.WriteLine("当前栈: ");
            foreach (char c in st)
            {
                Console.Write(c + " ");
            }
            Console.WriteLine();

            st.Push('e');
            st.Push('f');
            Console.WriteLine("栈顶元素: {0}",
            st.Peek());
            Console.WriteLine("当前栈: ");
            foreach (char c in st)
            {
                Console.Write(c + " ");
            }
            Console.WriteLine();

            Console.WriteLine("出栈 ");
            st.Pop();
            st.Pop();
            st.Pop();

            Console.WriteLine("当前栈: ");
            foreach (char c in st)
            {
                Console.Write(c + " ");
            }

            Console.ReadLine();
        }
        //------------------------------------------------------