mysql和php无限分类 数据归类 输出

说明在先：数据整合部分参考了网上博客；但是数据输出是自己写的，使用了递归；

数据归类解释：利用pid(子级)=id(父级)；让子级循环的时自己去找父级在哪儿，然后加入其中；

递归：里面需要注意，flag（|–）的问题，下一个父级兄弟要少一个flag(|–)

数据表结构：

CREATE TABLE `NewTable` (`id`  int(10) UNSIGNED NOT NULL AUTO_INCREMENT ,`pid`  int(10) UNSIGNED NOT NULL ,`name`  varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT '' ,PRIMARY KEY (`id`),INDEX `pid` (`pid`) USING BTREE )ENGINE=InnoDBDEFAULT CHARACTER SET=latin1 COLLATE=latin1_swedish_ciAUTO_INCREMENT=1ROW_FORMAT=COMPACT;

源数据

INSERT INTO `test1` VALUES (1, 0, 'menu1');INSERT INTO `test1` VALUES (2, 0, 'menu2');INSERT INTO `test1` VALUES (3, 0, 'menu3');INSERT INTO `test1` VALUES (4, 0, 'menu4');INSERT INTO `test1` VALUES (5, 0, 'menu5');INSERT INTO `test1` VALUES (6, 0, 'menu6');INSERT INTO `test1` VALUES (7, 1, 'menu1-1');INSERT INTO `test1` VALUES (8, 1, 'menu1-2');INSERT INTO `test1` VALUES (9, 1, 'menu1-3');INSERT INTO `test1` VALUES (10, 7, 'menu7-1');INSERT INTO `test1` VALUES (11, 7, 'menu7-2');INSERT INTO `test1` VALUES (12, 7, 'menu7-3');INSERT INTO `test1` VALUES (13, 7, 'menu7-4');INSERT INTO `test1` VALUES (14, 10, 'menu10-1');INSERT INTO `test1` VALUES (15, 10, 'menu10-2');INSERT INTO `test1` VALUES (16, 10, 'menu10-3');INSERT INTO `test1` VALUES (17, 8, 'menu8-1');

php代码：基于TP5框架

<?phpnamespace app\index\controller;use app\index\model;use think\Db;use think\Debug;class Index {    public function index()    {        $res = Db::table('test1')->select();        //新数组：自身id当作key，以便下面操作        $tree = array();        foreach ($res as $key => $val) {            $tree[$val['id']] = $val;            $tree[$val['id']]['children'] = array();        }        //将有pid的元素，整合到对应的pid=id（这一步是最重要的）        foreach ($tree as $key => $val) {            if ($val['pid'] != 0) {                $tree[$val['pid']]['children'][] = &$tree[$key];//$val['pid']=$key;等价于：pid=id            }        }        //去除tree中有pid的元素，因为他们已经被归类了；        foreach ($tree as $key => $val) {            if ($val['pid']==0) continue;             unset($tree[$key]);        }        $temp = array();        $grup = '';        $flag = '|--';        $this->recursive($tree,$temp,$grup,$flag);        var_dump($temp);exit;    }    public function recursive($data,&$temp,&$division,$flag)    {        $diviT = $division;        if(reset($data)['pid']!=0) $division .= $flag;        foreach ($data as $key => $val) {            $temp[] = $division.$val['name'];            if (is_array($val['children'])) {                $this->recursive($val['children'],$temp,$division,$flag);            }        }        $division = $diviT;        return false;    }}

新数组输出如下：

array(17) {  [0] => string(5) "menu1"  [1] => string(10) "|--menu1-1"  [2] => string(13) "|--|--menu7-1"  [3] => string(17) "|--|--|--menu10-1"  [4] => string(17) "|--|--|--menu10-2"  [5] => string(17) "|--|--|--menu10-3"  [6] => string(13) "|--|--menu7-2"  [7] => string(13) "|--|--menu7-3"  [8] => string(13) "|--|--menu7-4"  [9] => string(10) "|--menu1-2"  [10] => string(13) "|--|--menu8-1"  [11] => string(10) "|--menu1-3"  [12] => string(5) "menu2"  [13] => string(5) "menu3"  [14] => string(5) "menu4"  [15] => string(5) "menu5"  [16] => string(5) "menu6"}