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Home Backend Development PHP Tutorial 求多个父ID的情况下如何获取其下面的子ID的函数?

求多个父ID的情况下如何获取其下面的子ID的函数?

Jun 20, 2016 pm 12:38 PM

我在弄一个项目,需要多个父ID去查询其下面子ID的记录,写了个函数,只能查询单个父ID下面的,多个不知道怎么写了,没有思路,哪位帮下忙,在这谢过!奉上我自己写的函数:

function get_child_id($data, $parent_id = '0') {        static $child;        foreach ($data as $value) {            if ($value['parent_id'] == $parent_id) {                $child .= ',' . $value['cat_id'];                $this->get_child_id($data, $value['cat_id'], $level + 1);            }        }        return $child;    }
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回复讨论(解决方案)

循环调用你这个方法就可以了。

$parent_ids = array(1,2,3,4);$resul t= array();foreach($parent_ids as $parent_id){    $result[] = get_child_id($data, $parent_id);}function get_child_id($data, $parent_id = '0') {        static $child;        foreach ($data as $value) {            if ($value['parent_id'] == $parent_id) {                $child .= ',' . $value['cat_id'];                $this->get_child_id($data, $value['cat_id'], $level + 1);            }        }        return $child;    }
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对每个 父ID 都调用一下 get_child_id 不就行了?

不过 static $child; 会在多次调用时出问题的

多次循环 get_child_id会出现子栏目ID重复出现的情况

#2 我已经告诉你会出问题了
症结在 static $child; !

    function get_child_id($data, $parent_id = '0') {        $child = '';        foreach ($data as $value) {            if ($value['parent_id'] == $parent_id) {                $child .= ',' . $value['cat_id'];                $child .= $this->get_child_id($data, $value['cat_id'], $level + 1);            }        }        return $child;    }
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这个我发现了,但是还是会出现子栏目ID重复的情况

贴出你的测试数据,应该是 id 不唯一(没有死循环已经对你很客气了)

贴出你的测试数据,应该是 id 不唯一(没有死循环已经对你很客气了)


贴出你的测试数据,应该是 id 不唯一(没有死循环已经对你很客气了)
就是那个static问题,打开页面太多了,调试错了,不好意思啊版主!

我 #4 不是给你代码了吗?

我 #4 不是给你代码了吗?


看到了,也调试好了。谢谢版主
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