我用谷歌搜索了一些对我有用的东西(http://wizardinternetsolutions.com/web-database-design/dynamic-multilevel-css-menu-php-mysql/)。一旦我让它工作,我计划对其进行一些修改并根据我的需要进行调整。-Ej。我想label用作Primary Key而不是随机数。
但是,我收到一个错误: 警告:mysql_fetch_assoc() 期望参数 1 是资源,在第 23 行的 /home/content/81/10038181/html/_html/menu/menu-generator.php 中给出的布尔值
有趣的是,当我运行查询时,它运行良好。
这是表结构(SQL):
CREATE TABLE `menu` (
  `id` int(11) NOT NULL auto_increment,
  `label` varchar(50) NOT NULL default '',
  `link` varchar(100) NOT NULL default '#',
  `parent` int(11) NOT NULL default '0',
  `sort` int(11) default NULL,
  PRIMARY KEY  (`id`)
) ENGINE=MyISAM AUTO_INCREMENT=248 DEFAULT CHARSET=latin1;

PHP:
$dbc = new mysqli("localhost", "username", "password", "temp_database");
$dbn = "temp_database";
    function display_children($parent, $level) {
        $sql = "SELECT a.id, a.label, a.link, Deriv1.Count FROM `$dbn`.`menu` a  LEFT OUTER JOIN (SELECT `parent`, COUNT(`parent`) AS Count FROM `".$dbn."`.`menu` GROUP BY parent) Deriv1 ON a.id = Deriv1.parent WHERE a.parent=" . $parent . " ORDER BY `sort`";
        //echo $sql;  //For testing purposes
        $result = $dbc->query($sql);
        echo "<ul>\n";
        while ($row = $result->fetch_assoc() ) {
            if ($row['Count'] > 0) {
                echo "<li><a href='" . $row['link'] . "'>" . $row['label'] . "</a>";
                display_children($row['id'], $level + 1);
                echo "</li>";
                }
            elseif ($row['Count']==0) {
                echo "<li><a href='" . $row['link'] . "'>" . $row['label'] . "</a></li>";
                } 
            else;
        }
        echo "</ul>";
    }
    display_children(0, 1);