可以指针操作
unsafe标记非安全代码
非安全代码中可以使用指针
使用指针的时候表忘了fix

namespace ConsoleApplication1
{
    class Node<T>
    {
        private T data;
        private Node<T> next;

        public Node(T val, Node<T> p)
        {
            data = val;
            next = p;
        }

        public Node(Node<T> p)
        {
            next = p;
        }

        public Node(T val)
        {
            data = val;
            next = null;
        }

        public Node()
        {
            data = default(T);
            next = null;
        }

        public T Data
        {
            get
            {
                return data;
            }
            set
            {
                data = value;
            }
        }

        public Node<T> Next
        {
            get
            {
                return next;
            }
            set
            {
                next = value;
            }
        }

    }

    class LinkList<T>:IListDS<T>
    {
        private Node<T> head;

        public Node<T> Head
        {
            get
            {
                return head;
            }

            set
            {
                head = value;
            }
        }

        //构造器
        public LinkList()
        {
            head = null;
        }

        //求单链表的长度
        public int GetLength()
        {
            Node<T> p = head;

            int len = 0;
            while (p.Next != null)
            {
                ++len;
                p = p.Next;
            }
            return len;
        }

        //清空单链表
        public void Clear()
        {
            head = null;
        }

        //判断单链表是否为空
        public bool IsEmpty()
        {
            if (head == null)
            {
                return true;
            }
            else
            {
                return false;
            }
        }

        //在单链表的末尾添加新元素
        public void Append(T item)
        {
            Node<T> q = new Node<T>(item);
            Node<T> p = new Node<T>();

            if (head == null)
            {
                head = q;
                return;
            }

            p = head;
            while (p.Next != null)
            {
                p = p.Next;
            }

            p.Next = q;
        }

 //在单链表的第i个结点的位置前插入一个值为item的结点
        public void Insert(T item, int i)
        {
            if (IsEmpty() || i < 1)
            {
                Console.WriteLine("List is empty or Position is error!");
                return;
            }

            if (i == 1)
            {
                Node<T> q = new Node<T>(item);
                q.Next = head;
                head = q;
                return;
            }

            Node<T> p = head;
            Node<T> r = new Node<T>();
            int j = 1;

            while (p.Next != null && j < i)
            {
                
                p = p.Next;
                r = p;
                ++j;
            }

            if (j == i)
            {
                Node<T> q = new Node<T>(item);
                q.Next = p;
                r.Next = q;
            }
        }

        //在单链表的第i个结点的位置后插入一个值为item的结点
        public void InsertPost(T item, int i)
        {
            if (IsEmpty() || i < 1)
            {
                Console.WriteLine("List is empty or Position is error!");
                return;
            }

            if (i == 1)
            {
                Node<T> q = new Node<T>(item);
                q.Next = head.Next;
                head.Next = q;
                return;
            }

            Node<T> p = head;
            int j = 1;

            while (p != null && j < i)
            {
                p = p.Next;
                ++j;
            }

            if (j == i)
            {
                Node<T> q = new Node<T>(item);
                q.Next = p.Next;
                p.Next = q;
            }
        }

//删除单链表的第i个结点
        public T Delete(int i)
        {
            if (IsEmpty() || i < 0)
            {
                Console.WriteLine("Link is empty or Position is error!");
                return default(T);
            }

            Node<T> q = new Node<T>();
            if (i == 1)
            {
                q = head;
                head = head.Next;
                return q.Data;
            }

            Node<T> p = head;
            int j = 1;

            while (p!= null && j < i)
            {
                ++j;
                p = p.Next;
                q = p;
            }

            if (j == i)
            {
                q.Next = p.Next;
                return p.Data;
            }
            else
            {
                Console.WriteLine("The ith node is not exist!");
                return default(T);
            }
        }

        //获得单链表的第i个数据元素
        public T GetElem(int i)
        {
            if (IsEmpty())
            {
                Console.WriteLine("List is empty!");
                return default(T);
            }

            Node<T> p = new Node<T>();
            p = head;
            int j = 1;

            while (p.Next != null && j < i)
            {
                ++j;
                p = p.Next;
            }

            if (j == i)
            {
                return p.Data;
            }
            else
            {
                Console.WriteLine("The ith node is not exist!");
                return default(T);
            }
        }

        //在单链表中查找值为value的结点
        public int Locate(T value)
        {
            if (IsEmpty())
            {
                Console.WriteLine("List is Empty!");
                return -1;
            }

            Node<T> p = new Node<T>();
            p = head;
            int i = 1;
            while (!p.Data.Equals(value) && p.Next != null)
            {
                p = p.Next;
                ++i;
            }

            return i;
        } 


    }
}
里面用到了，泛型类，如果不懂，自己去查一下资料