js单向链表的具体实现实例

function linkNode(_key, _value)
{
    /// <summary>
    /// 链表类的节点类
    /// </summary>
    this.Key = _key;
    this.Value = _value;
    this.next = null;
}
function Link()
{
    /// <summary>
    /// 创建一个链表类
    /// </summary>
    this.root = new linkNode(null, null); //root永远是个空节点
    this.end = this.root;
}
Link.prototype =
{
    count: 0,
    value: function (_key)
    {
        /// <summary>
        /// 根据key的值来获取value值
        /// </summary>
        /// <param name="_key" type="String">
        /// key的值
        /// </param>
        /// <returns type="Object">
        /// 对应的value的值
        /// </returns>
        var i = this.root;
        while (Boolean(i = i.next))
        {
            if (i.Key == _key)
                return i.Value;
        }
    },
    add: function (_key, _value)
    {
        /// <summary>
        /// 往链表的尾部中加入一个节点
        /// </summary>
        /// <param name="_key" type="String">
        /// key的值
        /// </param>
        /// <param name="_value" type="Object">
        /// value的值
        /// </param>
        /// <returns type="Object">
        /// 返回新增加的value的值
        /// </returns>
        var i = this.root;
        while (Boolean(i = i.next))
        {
            if (i.Key == _key)
                return i.Value = _value;
        }
        var node = new linkNode(_key, _value);
        if (this.count == 0)
            this.root.next = node;
        else
            this.end.next = node;
        this.end = node;
        this.count++;
        return _value;
    },
    insert: function (_key, node)
    {
        /// <summary>
        /// 从链表类的某节点之后插入新节点node.
        /// </summary>
        /// <param name="_key" type="String">
        /// 在键值等于_key的元素之后插入
        /// </param>
        /// <param name="node" type="Object">
        /// 要插入的元素
        /// </param>
        var i = this.root;
        while (Boolean(i = i.next))
        {
            if (i.Key == _key)
            {
                var tmp = i.next;
                i.next = node;
                node.next = tmp;
                break;
            }
        }
    },
    insertBefore: function (_key, node)
    {
        /// <summary>
        /// 从链表类的某节点之后插入新节点node.
        /// </summary>
        /// <param name="_key" type="String">
        /// 在键值等于_key的元素之后插入
        /// </param>
        /// <param name="node" type="Object">
        /// 要插入的元素 www.jb51.net
        /// </param>
        var i = this.root;
        while (Boolean(i = i.next))
        {
            if (i.next.Key == _key)
            {
                var tmp = i.next;
                i.next = node;
                node.next = tmp;
                break;
            }
        }
    },
    remove: function (_key)
    {
        /// <summary>
        /// 从链表类中移除一个key
        /// </summary>
        /// <param name="_key" type="String">
        /// key的值
        /// </param>
        var i = this.root;
        do
        {
            if (i.next.Key == _key)
            {
                if (i.next.next == null)
                    this.end = i;
                i.next = i.next.next;

                this.count--;
                return;
            }
        } while (Boolean(i = i.next))
    },
    exists: function (_key)
    {
        /// <summary>
        /// 检查链表类中是否存在一个key
        /// </summary>
        /// <param name="_key" type="String">
        /// key的值
        /// </param>
        /// <returns type="Boolean">
        /// </returns>
        var i = this.root;
        while (Boolean(i = i.next))
            if (i.Key == _key)
                return true;
        return false;
    },
    removeAll: function ()
    {
        /// <summary>
        /// 清空链表类
        /// </summary>
        this.root = new linkNode(null, null);
        this.end = this.root;
        this.count = 0;
    },
    Obj2str: function (o)
    {
        if (o == undefined)
        {
            return "";
        }
        var r = [];
        if (typeof o == "string")
            return "\"" + o.replace(/([\"\\])/g, "\\$1").replace(/(\n)/g, "\\n").replace(/(\r)/g, "\\r").replace(/(\t)/g, "\\t") + "\"";
        if (typeof o == "object")
        {
            if (!o.sort)
            {
                for (var i in o)
                    r.push("\"" + i + "\":" + this.Obj2str(o[i]));
                r = "{" + r.join() + "}";
            }
            else
            {
                for (var i = 0; i < o.length; i++)
                    r.push(this.Obj2str(o[i]))
                r = "[" + r.join() + "]";
            }
            return r;
        }
        return o.toString().replace(/\"\:/g, '":""');
    },
    getJSON: function ()
    {
        /// <summary>
        /// 转换成JSON字符串
        /// </summary>
        /// <returns type="String">
        /// </returns>
        //内部方法，用于递归
        var me = this;
        var getChild = function (node)
        {
            var str = "";
            str += "{\"Key\":\"" + node.Key + "\",\"Value\":" + me.Obj2str(node.Value);
            if (node.next != null)
                str += ",\"next\":" + getChild(node.next);
            else
                str += ",\"next\":\"null\"";
            str += "}";
            return str;
        };
        var link = "{\"root\":{\"Key\":\"null\",\"Value\":\"null\",\"next\":";
        if (this.count == 0)//如果空表
        {
            return "{\"root\":{\"Key\":\"null\",\"Value\":\"null\",\"next\":\"null\"},\"end\":{\"Key\":\"null\",\"Value\":\"null\",\"next\":\"null\"},\"count\":\"0\"}";
        }
        link += getChild(this.root.next) + "}";
        //加上end
        link += ",\"end\":{\"Key\":\"" + this.end.Key + "\",\"Value\":" + me.Obj2str(this.end.Value) + ",\"next\":\"null\"";
        link += "},\"count\":\"" + this.count + "\"}";
        return link;
    },
    getArrayJSON: function ()
    {
        /// <summary>
        /// 转所有节点的value换成JSON字符串,数组格式
        /// </summary>
        /// <returns type="String">
        /// </returns>
        var link = "{\"link\":[";
        var i = this.root;
        while (Boolean(i = i.next))
        {
            link += this.Obj2str(i.Value) + ",";
        }
        link = link.substr(0, link.length - 1);
        link += "]}";
        return link;
    },
    sort: function (fn)
    {
        /// <summary>
        /// 对链表进行排序
        /// </summary>
        /// <param name="fn" type="Function">
        /// 比较两个链表元素大小的方法，当返回真时，此方法的参数所指的节点将往下沉
        /// </param>
        if (fn != null)
        {

            var i = this.root;
            while (Boolean(i = i.next))
            {
                var j = this.root;
                while (Boolean(j = j.next))
                {
                    if (j.next != null)
                    {
                        if (fn.call(this, j))
                        {
                            var Key = j.Key;
                            var Value = j.Value;
                            j.Key = j.next.Key;
                            j.Value = j.next.Value;
                            j.next.Key = Key;
                            j.next.Value = Value;
                        }
                    }
                }
                this.end = i;
            }

        }
        else
        {

        }
    }
};