创建列表类

<?php
/**
 * Created by PhpStorm.
 * User: zooeymoon
 * Date: 2018/5/6
 * Time: 15:06
 */

class Lists{

    public $elements = [];
    public $pos;

    public function __construct()
    {
        $this->pos = 0;
    }

    /**
     * 清空列表元素
     */
    public function clear()
    {
        $this->elements = [];
        $this->pos = 0;
    }

    /**
     * 向列表中添加元素
     * @param $element 元素
     */
    public function append($element)
    {
        $this->elements[$this->getSize()] = $element;
    }

    /**
     * 输出列表元素
     */
    public function toString()
    {
        echo implode(",",$this->elements);
    }

    /**
     * 删除列表中的元素
     * 成功返回true
     * @param $element 要删除的元素
     * @return bool
     */
    public function remove($element)
    {
        $foundAt = $this->find($element);

        if($foundAt > -1){
            array_splice($this->elements,$foundAt,1);
            return true;
        }

        return false;
    }


    /**
     * 查找元素是否在列表中存在
     * 存在返回元素位置，不存在返回-1
     * @param $element
     * @return int
     */
    public function find($element)
    {
        for($i = 0 ; $i < $this->getSize() ; $i++){
            if($this->elements[$i] == $element){
                return $i;
            }
        }

        return -1;
    }

    /**
     * 返回列表元素的数量
     * @return int
     */
    public function getSize()
    {
        return count($this->elements);
    }

    /**
     * 返回当前列表指针位置
     * @return int
     */
    public function getCurrentPosition()
    {
        return $this->pos + 1;
    }

    /**
     * 插入元素
     * @param $element
     * @param $after
     * @return bool
     */
    public function insert($element,$after)
    {
        $insertPos = $this->find($after);

        if($insertPos > -1){
            array_splice($this->elements,$insertPos+1,0,$element);
            return true;
        }

        return false;
    }

    /***
     * 查找某个元素是否在列表中
     * @param $element
     * @return bool
     */
    public function contains($element)
    {

        return in_array($element,$this->elements);

    }

    public function front()
    {
        $this->pos = 0;
    }

    public function end()
    {
        $this->pos = count($this->elements)-1;
    }

    public function prev()
    {
        if($this->hasPrev()){
            $this->pos--;
            return true;
        }

        return false;
    }

    public function next()
    {
        if($this->hasNext()){
            $this->pos++;
            return true;
        }

        return false;
    }

    public function hasNext()
    {
        return $this->pos < count($this->elements)-1;
    }

    public function hasPrev()
    {
        return $this->pos > 0;
    }

    public function moveTo($position){

        if($position > 0){

            if($position-1 <= count($this->elements)){
                $this->pos = $position - 1;
                return true;
            }
        }

        return false;

    }

    public function getElement()
    {
        return $this->elements[$this->pos];
    }


}

class Person{
    public $name;
    public $sex;

    public function __construct($name,$sex)
    {
        $this->name = $name;
        $this->sex = $sex;
    }
}


$list = new Lists();
$list->append(new Person("liwenqiang",1));
$list->append(new Person("haha",1));
$list->append(new Person("whatever",2));
$list->append(new Person("hehe",1));

function getSameSexName($list , $sex){
    for($list->front();$list->hasNext();$list->next()){
        if($list->getElement()->sex == $sex){
            echo $list->getElement()->name;
        }
    }
}

getSameSexName($list,1);