php中的菜单显示

Question

我从管理端创建CMC页面。我在前端有一个3级菜单。我的CMS页面的数据库表结构的字段为name,parent_id,description, status。

现在我必须在菜单中显示子页面的所有页面，子页面和子页面。如何编写这个查询？

<!-- BEGIN Menu --> 
    <ul id="nav"> 
<li><a href="consumers.php">Consumers</a> 
    <ul><li><a href="personal_finance.php">Personal Finance </a> 
<ul><li><a href="personal_financial_makeover.php">Personal Financial Makeover</a></li> 
     <li><a href="personal_finance_consultancy.php">Personal Finance Consultancy</a></li> 
     </ul> 
    </li> 
    <li><a href="investings.php">Investings</a> 
     <ul> 
    <li><a href="securities_analysis.php">Securities Analysis</a></li> 
     <li><a href="portfolio_investment.php">Bernie Madoff Shield (Portfolio and Investment Analysis)</a></li> 
    </ul> 
    </li> 
    </ul> 
      </li> 
     <li><a href="entrepreneurs.php">Entrepreneurs</a> 
      <ul> 
    <li><a href="market_analysis.php">Market Analysis and Competitive Report </a></li> 
       <li><a href="business_plans_feasibility.php">Business Plans &amp; Feasibility Studies </a> 
      <ul> 
      <li><a href="business_plans.php">Business Plans</a> 
        <ul> 
         <li><a href="level1.php">Level 1</a></li> 
         <li><a href="level2.php">Level 2</a></li> 
         <li><a href="level3.php">Level 3</a></li> 
        </ul> 

        </li> 
     </ul> 

     </li> 
        </ul> 

    <!-- END Menu --> 

---

像你说的我试过了。我有主页。它没有孩子。它仍然是空的下拉菜单。然后正确显示一级菜单。并且还显示第二级菜单。实际上鼠标悬停在firstlevel菜单下拉菜单上。我正在下拉。直到现在好。但公开显示菜单名称。请看我的附件。我附上了2张图片。在第一张图像直接显示像这样。在鼠标悬停在第一级显示下拉第二图像。

<? 

$query = "SELECT 
    t1.auto_id AS l1_id, t1.name AS l1_name 
    ,t2.auto_id AS l2_id, t2.name AS l2_name 
    ,t3.auto_id AS l3_id, t3.name AS l3_name 
FROM static_pages AS t1 
LEFT JOIN static_pages AS t2 ON t2.parent_id = t1.auto_id 
LEFT JOIN static_pages AS t3 ON t3.parent_id = t2.auto_id"; 

$result = mysql_query($query); 

$results = array() ; 
while($row=mysql_fetch_assoc($result)){ 
    $results[] = $row; 
} 

// Building the menu. Quick and dirty. 
$menu = array() ; 
foreach($results as $result) { 
    $menu_level_3 = array('auto_id' => $result['l3_id'], 'name' => $result['l3_name'], 'children' => array()) ; 
    $menu_level_2 = array('auto_id' => $result['l2_id'], 'name' => $result['l2_name'], 'children' => array($menu_level_3['auto_id'] => $menu_level_3)) ; 
    $menu_level_1 = array('auto_id' => $result['l1_id'], 'name' => $result['l1_name'], 'children' => array($menu_level_2['auto_id'] => $menu_level_2)) ; 

    if(!isset($menu[$menu_level_1['auto_id']])) { 
     $menu[$menu_level_1['auto_id']] = $menu_level_1 ; 
    } elseif(!isset($menu[$menu_level_1['auto_id']]['children'][$menu_level_2['auto_id']])) { 
     $menu[$menu_level_1['auto_id']]['children'][$menu_level_2['auto_id']] = $menu_level_2 ; 
    } else { 
     $menu[$menu_level_1['auto_id']]['children'][$menu_level_2['auto_id']]['children'][$menu_level_3['auto_id']] = $menu_level_3; 
    } 
} 
?> 
<ul id="nav"> 
<? foreach($menu as $item0) : ?> 
    <li> 
    <a href="?page=<?=$item0['auto_id']?>"><?=$item0['name']?></a> 
    <? if(!empty($item0['children'])){?> 
    <ul> 
    <? foreach($item0['children'] as $item1) : ?> 
     <li> 
     <a href="?page=<?=$item1['auto_id']?>"><?=$item1['name']?></a> 
     <? if(!empty($item1['children'])){?> 
     <ul> 
     <? foreach($item1['children'] as $item2) : ?> 
      <li><a href="?page=<?=$item2['auto_id']?>"><?=$item2['name']?></a></li> 
     <? endforeach; ?> 
     </ul> 
     <? }?> 
     </li> 
    <? endforeach; ?> 
    </ul> 
    <? }?> 
    </li> 
<? endforeach;exit;?> 
</ul> 

Answer 1

我建议你阅读Managing Hierarchical Data in MySQL。

的查询是：

SELECT t1.name AS lev1, t2.name as lev2, t3.name as lev3 
FROM pages AS t1 
LEFT JOIN pages AS t2 ON t2.parent = t1.pages_id 
LEFT JOIN pages AS t3 ON t3.parent = t2.pages_id; 

UPDATE

$query = ' 
SELECT 
    t1.pages_id AS l1_id, t1.name AS l1_name 
    ,t2.pages_id AS l2_id, t2.name AS l2_name 
    ,t3.pages_id AS l3_id, t3.name AS l3_name 
FROM pages AS t1 
LEFT JOIN pages AS t2 ON t2.parent = t1.pages_id 
LEFT JOIN pages AS t3 ON t3.parent = t2.pages_id 
'; 

$result = mysql_query($query); 

$results = array() ; 
while($row=mysql_fetch_assoc($result)){ 
    $results[] = $row; 
} 

// Building the menu. Quick and dirty. 
$menu = array() ; 
foreach($results as $result) { 
    $menu_level_3 = array('id' => $result['l3_id'], 'name' => $result['l3_name'], 'children' => array()) ; 
    $menu_level_2 = array('id' => $result['l2_id'], 'name' => $result['l2_name'], 'children' => array($menu_level_3['id'] => $menu_level_3)) ; 
    $menu_level_1 = array('id' => $result['l1_id'], 'name' => $result['l1_name'], 'children' => array($menu_level_2['id'] => $menu_level_2)) ; 

    if(!isset($menu[$menu_level_1['id']])) { 
     $menu[$menu_level_1['id']] = $menu_level_1 ; 
    } elseif(!isset($menu[$menu_level_1['id']]['children'][$menu_level_2['id']])) { 
     $menu[$menu_level_1['id']]['children'][$menu_level_2['id']] = $menu_level_2 ; 
    } else { 
     $menu[$menu_level_1['id']]['children'][$menu_level_2['id']]['children'][$menu_level_3['id']] = $menu_level_3; 
    } 
} 
?> 
<ul> 
<? foreach($menu as $item0) : ?> 
    <li> 
    <a href="?page=<?=$item0['id']?>"><?=$item0['name']?></a> 
    <ul> 
    <? foreach($item0['children'] as $item1) : ?> 
     <li> 
     <a href="?page=<?=$item1['id']?>"><?=$item1['name']?></a> 
     <ul> 
     <? foreach($item1['children'] as $item2) : ?> 
      <li><a href="?page=<?=$item2['id']?>"><?=$item2['name']?></a></li> 
     <? endforeach; ?> 
     </ul> 
     </li> 
    <? endforeach; ?> 
    </ul> 
    </li> 
<? endforeach; ?>