PHP 擷取數組任意下標key的上一個prev和下一個next下標值

標籤：php 擷取數組任意下標key

PHP 擷取數組任意下標key的上一個prev和下一個next下標值

<?php$xoops[1] = '小';$xoops[2] = '孩';$xoops[3] = '子';$xoops[4] = '氣';$steps = new Steps();foreach($xoops as $key=>$value){$steps->add($key);}$steps->setCurrent(3);//參數為key值echo '上一個下標：'.$steps->getPrev()."<br />";echo '指定的下標：'.$steps->getCurrent()."<br />";echo '下一個下標：'.$steps->getNext()."<br />";class Steps {     private $all;    private $count;    private $curr;     function __construct() {        $this->count = 0;    }    function add($step) {        $this->count++;        $this->all[$this->count] = $step;    }    function setCurrent($step) {        reset($this->all);        for ($i = 1; $i <= $this->count; $i++) {            if ($this->all[$i] == $step)                break;            next($this->all);        }        $this->curr = current($this->all);    }    function getCurrent() {        return $this->curr;    }    function getNext() {        self::setCurrent($this->curr);        return next($this->all);    }    function getPrev() {        self::setCurrent($this->curr);        return prev($this->all);    }}

列印結果：

上一個下標：2指定的下標：3下一個下標：4