无限级分类，级分类
public function getlist($pid = 0, &$result=array(), $spac = 0){<br> $spac += 2;<br> $list = M('liuyan')->where('pid='.$pid)->select();<br> foreach($list as $val){<br> $val['content'] = str_repeat('',$spac).$val['content'];<br> $result[] = $val;<br> $this->getlist($val['id'], $result, $spac);<br> }<br> return $result;<br>}Copy after login
function genTree($items,$id='id',$pid='pid',$son = 'children'){
$tree = array();
$tmpMap = array();
foreach ($items as $item) {
$tmpMap[$item[$id]] = $item;
}
foreach ($items as $item) {
if (isset($tmpMap[$item[$pid]])) {
$tmpMap[$item[$pid]][$son][] = &$tmpMap[$item[$id]];
} else {
$tree[] = &$tmpMap[$item[$id]];
}
}
unset($tmpMap);
return $tree;
}
$items1 = array(
array('id' => 1, 'pid' => 0, 'name' => '一级11' ),
array('id' => 11, 'pid' => 0, 'name' => '一级12' ),
array('id' => 2, 'pid' => 1, 'name' => '二级21' ),
array('id' => 10, 'pid' => 11, 'name' => '二级22' ),
array('id' => 3, 'pid' => 1, 'name' => '二级23' ),
array('id' => 12, 'pid' => 11, 'name' => '二级24' ),
array('id' => 9, 'pid' => 1, 'name' => '二级25' ),
array('id' => 14, 'pid' => 1, 'name' => '二级26' ),
array('id' => 4, 'pid' => 9, 'name' => '三级31' ),
array('id' => 6, 'pid' => 9, 'name' => '三级32' ),
array('id' => 7, 'pid' => 4, 'name' => '四级41' ),
array('id' => 8, 'pid' => 4, 'name' => '四级42' ),
array('id' => 5, 'pid' => 4, 'name' => '四级43' ),
array('id' => 13, 'pid' => 4, 'name' => '四级44' ),
array('id' => 15, 'pid' => 8, 'name' => '五级51' ),
array('id' => 16, 'pid' => 8, 'name' => '五级52' ),
array('id' => 17, 'pid' => 8, 'name' => '五级53' ),
array('id' => 18, 'pid' => 16, 'name' => '六级64' ),
);
var_dump(genTree($items1));
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