C# 顺序栈

    public interface IStack<T>
    {
        int GetLength();
        bool IsEmpty();
        bool IsFull();
        void Clear();
        void Push(T item);
        T Pop();
        T GetTop();
    }


    public class Stack<T> : IStack<T>
    {
        private int size;
        private T[] data;
        private int top;

        public T this[int index]
        {
            get
            {
                return data[index];
            }
            set
            {
                data[index] = value;
            }
        }

        public int GetSize
        {
            get
            {
                return size;
            }
            set
            {
                size = value;
            }
        }

        public int Top
        {
            get
            {
                return top;
            }
        }

        public Stack(int size)
        {
            data = new T[size];
            top = -1;
            this.size = size;
        }

        public int GetLength()
        {
            return top + 1;
        }

        public bool IsEmpty()
        {
            if (top == -1)
            {
                return true;
            }
            else
            {
                return false;
            }
        }

        public bool IsFull()
        {
            if (top == size -1)
            {
                return true;
            }
            else
            {
                return false;
            }
        }

        public void Clear()
        {
            top = -1;
        }

        public void Push(T item)
        {
            if (IsFull())
            {
                throw new Exception("Stack is full, can't push any item");
            }
            else
            {
                data[++top] = item;
            }
        }

        public T Pop()
        {
            T temp = data[top];
            if (IsEmpty())
            {
                throw new Exception("Stack is empty, can't pop out anything.");
            }
            top--;
            return temp;
        }

        public T GetTop()
        {
            if (IsEmpty())
            {
                throw new Exception("Stack is empty, can't get top item.");                
            }
            return data[top];
        }
    }