php递归获取分类结构

喜欢ヅ旅行 2022-12-11 11:24 166阅读 0赞

PHP递归获取分类结构：

/** * 两个大类：电脑、手机 * --手机{三星Glaxy,IphoneX,华为荣耀} * --电脑{Dell,Lenovo,IBM} */
    $data = array(
        array('id' => 1, 'name' => '手机', 'pid' => 0),
        array('id' => 2, 'name' => '三星Glaxy', 'pid' => 1),
        array('id' => 3, 'name' => 'IphoneX', 'pid' => 1),
        array('id' => 4, 'name' => '华为荣耀', 'pid' => 1),
        array('id' => 5, 'name' => '电脑', 'pid' => 0),
        array('id' => 6, 'name' => 'Dell', 'pid' => 5),
        array('id' => 7, 'name' => 'Lenovo', 'pid' => 5),
        array('id' => 8, 'name' => 'IBM', 'pid' => 5)
    );
    
    /** * 递归获取结构树 * @param array $data 数据源 * @param integer $pid 父类id * @param integer $level 深度 * @return array 组装好的树 */
    function get_tree($data, $pid = 0, $level = 0) { 
        static $tree = array();
        foreach ($data as $key => $row) { 
            if ($row['pid'] == $pid) { 
                $row['level'] = $level;
                $tree[] = $row;
                unset($data[$key]); //进入树结构后，接下里要查的就只是它的子类了，所以从$data中删除，减少后面查询次数
                get_tree($data, $row['id'], $level + 1);
            }
        }
        return $tree;
    }
    
    /** * 输出树结构 * @param array 数据源 * @return void */
    function echo_tree($tree) { 
        foreach ($tree as $row) { 
            for ($i = $row['level']; $i > 0; $i--) { 
                echo '|----';
            }
            echo $row['name'];
            echo '<br>';
        }
    }
    
    $tree = get_tree($data, 0, 0);
    var_dump($tree);
    echo "<hr>";
    echo_tree($tree);
    echo "<\n>";

执行结果：

array(8) {
      [0]=>
      array(4) {
        ["id"]=>
        int(1)
        ["name"]=>
        string(6) "手机"
        ["pid"]=>
        int(0)
        ["level"]=>
        int(0)
      }
      [1]=>
      array(4) {
        ["id"]=>
        int(2)
        ["name"]=>
        string(11) "三星Glaxy"
        ["pid"]=>
        int(1)
        ["level"]=>
        int(1)
      }
      [2]=>
      array(4) {
        ["id"]=>
        int(3)
        ["name"]=>
        string(7) "IphoneX"
        ["pid"]=>
        int(1)
        ["level"]=>
        int(1)
      }
      [3]=>
      array(4) {
        ["id"]=>
        int(4)
        ["name"]=>
        string(12) "华为荣耀"
        ["pid"]=>
        int(1)
        ["level"]=>
        int(1)
      }
      [4]=>
      array(4) {
        ["id"]=>
        int(5)
        ["name"]=>
        string(6) "电脑"
        ["pid"]=>
        int(0)
        ["level"]=>
        int(0)
      }
      [5]=>
      array(4) {
        ["id"]=>
        int(6)
        ["name"]=>
        string(4) "Dell"
        ["pid"]=>
        int(5)
        ["level"]=>
        int(1)
      }
      [6]=>
      array(4) {
        ["id"]=>
        int(7)
        ["name"]=>
        string(6) "Lenovo"
        ["pid"]=>
        int(5)
        ["level"]=>
        int(1)
      }
      [7]=>
      array(4) {
        ["id"]=>
        int(8)
        ["name"]=>
        string(3) "IBM"
        ["pid"]=>
        int(5)
        ["level"]=>
        int(1)
      }
    }

输出树结构：  
![在这里插入图片描述][20210125145501205.png]

--------------------

获取子树：

/** * 获取子树 * @param $array * @param int $id * @return array */
     function getTree($array, $id=0)
    { 
        $tree = array();
        foreach ($array as $key => $value) { 
            if (in_array($id, explode(',',$value['pid']))) { 
                $value['children'] = getTree($array, $value['id']);
                if (!$value['children']) { 
                    unset($value['children']);
                }
                $tree[] = $value;
            }
        }
        return $tree;
    }
    
    $tree2 = getTree($data, 0);
    var_dump($tree2);

执行结果：

array(2) {
      [0]=>
      array(4) {
        ["id"]=>
        int(1)
        ["name"]=>
        string(6) "手机"
        ["pid"]=>
        int(0)
        ["children"]=>
        array(3) {
          [0]=>
          array(3) {
            ["id"]=>
            int(2)
            ["name"]=>
            string(11) "三星Glaxy"
            ["pid"]=>
            int(1)
          }
          [1]=>
          array(3) {
            ["id"]=>
            int(3)
            ["name"]=>
            string(7) "IphoneX"
            ["pid"]=>
            int(1)
          }
          [2]=>
          array(3) {
            ["id"]=>
            int(4)
            ["name"]=>
            string(12) "华为荣耀"
            ["pid"]=>
            int(1)
          }
        }
      }
      [1]=>
      array(4) {
        ["id"]=>
        int(5)
        ["name"]=>
        string(6) "电脑"
        ["pid"]=>
        int(0)
        ["children"]=>
        array(3) {
          [0]=>
          array(3) {
            ["id"]=>
            int(6)
            ["name"]=>
            string(4) "Dell"
            ["pid"]=>
            int(5)
          }
          [1]=>
          array(3) {
            ["id"]=>
            int(7)
            ["name"]=>
            string(6) "Lenovo"
            ["pid"]=>
            int(5)
          }
          [2]=>
          array(3) {
            ["id"]=>
            int(8)
            ["name"]=>
            string(3) "IBM"
            ["pid"]=>
            int(5)
          }
        }
      }
    }

通过递归返回层级数组：

/** * 根据id通过递归返回层级数组 * @param $lists * @param $id * @return array */
     function getChildren($lists, $id) { 
        $list = [];
        $i =  0;
        foreach($lists as $value) { 
            if(in_array($id, explode(',',$value['pid']))) { 
                $list[$i] = $value;
                $list[$i]['children'] = getChildren($lists, $value['id']);
            }
            $i++;
        }
        if($list) { 
            $list = array_values($list);
            return $list;
        } else { 
            return [];
        }
    }
    
    $tree3 = getChildren($data, 0);
    var_dump($tree3);

执行结果：

array(2) {
      [0]=>
      array(4) {
        ["id"]=>
        int(1)
        ["name"]=>
        string(6) "手机"
        ["pid"]=>
        int(0)
        ["children"]=>
        array(3) {
          [0]=>
          array(4) {
            ["id"]=>
            int(2)
            ["name"]=>
            string(11) "三星Glaxy"
            ["pid"]=>
            int(1)
            ["children"]=>
            array(0) {
            }
          }
          [1]=>
          array(4) {
            ["id"]=>
            int(3)
            ["name"]=>
            string(7) "IphoneX"
            ["pid"]=>
            int(1)
            ["children"]=>
            array(0) {
            }
          }
          [2]=>
          array(4) {
            ["id"]=>
            int(4)
            ["name"]=>
            string(12) "华为荣耀"
            ["pid"]=>
            int(1)
            ["children"]=>
            array(0) {
            }
          }
        }
      }
      [1]=>
      array(4) {
        ["id"]=>
        int(5)
        ["name"]=>
        string(6) "电脑"
        ["pid"]=>
        int(0)
        ["children"]=>
        array(3) {
          [0]=>
          array(4) {
            ["id"]=>
            int(6)
            ["name"]=>
            string(4) "Dell"
            ["pid"]=>
            int(5)
            ["children"]=>
            array(0) {
            }
          }
          [1]=>
          array(4) {
            ["id"]=>
            int(7)
            ["name"]=>
            string(6) "Lenovo"
            ["pid"]=>
            int(5)
            ["children"]=>
            array(0) {
            }
          }
          [2]=>
          array(4) {
            ["id"]=>
            int(8)
            ["name"]=>
            string(3) "IBM"
            ["pid"]=>
            int(5)
            ["children"]=>
            array(0) {
            }
          }
        }
      }
    }

--------------------

**参考文章地址：**

*  [https://www.cnblogs.com/zjfblog/p/8888510.html][https_www.cnblogs.com_zjfblog_p_8888510.html]
 *  [https://blog.csdn.net/dianai7709/article/details/101517199][https_blog.csdn.net_dianai7709_article_details_101517199]
 *  [https://blog.csdn.net/qq\_41564405/article/details/89539818][https_blog.csdn.net_qq_41564405_article_details_89539818]

[20210125145501205.png]: /images/20221123/2f7a3b7136aa49289a1c0cc887732546.png
[https_www.cnblogs.com_zjfblog_p_8888510.html]: https://www.cnblogs.com/zjfblog/p/8888510.html
[https_blog.csdn.net_dianai7709_article_details_101517199]: https://blog.csdn.net/dianai7709/article/details/101517199
[https_blog.csdn.net_qq_41564405_article_details_89539818]: https://blog.csdn.net/qq_41564405/article/details/89539818