PHP 递归实现层级树状展现数据
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<?php$db = mysql_connect('localhost', 'root', 'root') or die('Can\'t connect to database');mysql_select_db('test') or die('Can\'t find database : test');$result = mysql_query('select id, fid, name from tree');while($arr = mysql_fetch_array($result)){ $data[] = array( 'id' => $arr['id'], 'fid' => $arr['fid'], 'name' => $arr['name'], );}// 将数据按照缩进简单排列 见图1function data2arr($tree, $rootId = 0, $level = 0) { foreach($tree as $leaf) { if($leaf['fid'] == $rootId) { echo str_repeat(' ', $level) . $leaf['id'] . ' ' . $leaf['name'] . '<br/>'; foreach($tree as $l) { if($l['fid'] == $leaf['id']) { data2arr($tree, $leaf['id'], $level + 1); break; } } } }}data2arr($data);echo '<br/>-----------------------------------<br/>';// 将数据按照所属关系封装 见图2function arr2tree($tree, $rootId = 0) { $return = array(); foreach($tree as $leaf) { if($leaf['fid'] == $rootId) { foreach($tree as $subleaf) { if($subleaf['fid'] == $leaf['id']) { $leaf['children'] = arr2tree($tree, $leaf['id']); break; } } $return[] = $leaf; } } return $return;}$tree = arr2tree($data);print_r($tree);echo '<br/>-----------------------------------<br/>';// 将数据使用HTML再次展现 见图3function tree2html($tree) { echo '<ul>'; foreach($tree as $leaf) { echo '<li>' .$leaf['name']; if(! empty($leaf['children'])) tree2html($leaf['children']); echo '</li>'; } echo '</ul>';}tree2html($tree);?
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