html lists - PHP Generate UL LI , UL LI

Question

不知道如何使用while循环生成此菜单

这是我的代码的一个例子:

<ul id="nav">
<li><a href="#">Hoofdmenu 1</a>
<ul class="sub">
        <li><a href="#">Submenu 1.1</a></li>
        <li><a href="#">Submenu 1.2</a></li>
        <li><a href="#">Submenu 1.3</a></li>
        <li><a href="#">Submenu 1.4</a></li>
    </ul>
</li>
<li><a href="#">Hoofdmenu 2</a>
    <ul class="sub">
        <li><a href="#">Submenu 2.1</a></li>
        <li><a href="#">Submenu 2.2</a></li>
        <li><a href="#">Submenu 2.3</a></li>
        <li><a href="#">Submenu 2.4</a></li>
    </ul>
</li>
</ul>

我的表看起来像:

paginas:
    id
    title
    content
    type

当type == id来自父菜单时，它应该是子菜单。在我的例子中这是可行的，现在我要把它变成动态的。脑子也不工作了。

谢谢你的帮助!

使用代码从db:

获取数据

<ul id="nav">
<?php
include_once("ond/inc/php/connect.php");
$query = "SELECT * FROM paginas WHERE type = '0'";
$result = mysql_query($query);
while($row = mysql_fetch_object($result)){
echo '<li><a href="?ond='.$row->titel.'">'.$row->titel.'</a>';}
echo '<ul class="sub">';
$query2 = "SELECT * FROM paginas WHERE type = '".$row->id."'";
$result2 = mysql_query($query2);    
while($row2 = mysql_fetch_object($result2))
{
    echo '<li><a href="?ond='.$row2->titel.'">'.$row2->titel.'</a></li>';
}
echo '</ul>'; 
echo '</li>';
?>
</ul>

Answer 1

我会这样做:

首先，将数据作为数组取出，并对每个条目进行循环。然后运行如下命令:

$menuArray = array();
if (empty($type)) // If the entry has no "type", then it's a parent
{
    $menuArray[$type]['title'] = $title;
}
else // else, it's a child, so append it to the parent
{
    $menuArray[$type]['subitems'][] = $title;
}

然后，通过$menuArray循环创建菜单:

?><ul id="nav"><?php
foreach ($menuArray as $item)
{
    ?><li><a href="#">$item['title']</a><?php
    ?><ul class="sub"><?php
    foreach ($item['subitems'] as $subItem)
    {
        <li><a href="#">$subItem</a></li>
    }
    ?></ul><?php
    ?></li><?php
}
?></ul><?php

Answer 2

下一行是解决方案:

<ul id="nav">
<?php
include_once("ond/inc/php/connect.php");
$query = "SELECT * FROM paginas WHERE type = '0'";
$result = mysql_query($query);
while($row = mysql_fetch_object($result)){
echo '<li><a href="?ond='.$row->titel.'">'.$row->titel.'</a>';
$query2 = "SELECT * FROM paginas WHERE type = '".$row->id."'";
$result2 = mysql_query($query2);    
echo '<ul class="sub">';
while($row2 = mysql_fetch_object($result2))
{   
    echo '<li><a href="?ond='.$row2->titel.'">'.$row2->titel.'</a></li>';

}
    echo '</ul>';
echo '</li>';}

?>
</ul>

Answer 3

function load()
{
    global $conn;

    $query = "SELECT *  FROM sub_category WHERE main_category_id='1'";
    $result = mysqli_query($conn,$query);
    while($row = mysqli_fetch_assoc($result)){
        $cat_id=$row['sub_category_id'];
    echo '<li><a href="?id='.$row['sub_category_id'].'">'.$row['sub_category_name'].'</a>';
    $query2 = "SELECT *  FROM categories WHERE sub_category_id='$cat_id'";
    $result2 = mysqli_query($conn,$query2);    
    echo '<ul class="sub">';
    while($row2 = mysqli_fetch_assoc($result2))
    {   
        echo '<li><a href="?id='.$row2['category_id'].'">'.$row2['category_name'].'</a></li>';

    }
        echo '</ul>';
    echo '</li>';}

}

Answer 4

在这个例子中使用了parent_id列和使用引用构建的ul-li列表—它只进行1次SQL查询并使用递归呈现输出，这段代码可以根据您的需要简单地更改

        <?php
 /**
  * Module for displaying data from items table
  */
class App_Modules_Tree  extends   App_AbstractModule {
    /**
        * array for storing data
        *
        * @var array
        */
    private $tree = array();
       /**
        * html - output of current module
        *
        * @var string
        */
        private $output = ''; 
      /**
       * Retreives data from table items.
       *
       * @return void
       */
        private function _getData()
    {
        $pdo = App_Registry::get('pdo');
        $levels = array();
        foreach ($pdo->query('SELECT * FROM items ORDER BY parent_id ASC',PDO::FETCH_OBJ) as $k=>$v){
                   // references
             $current =  &$levels[ $v->id ] ;
                 $current['parent_id'] = $v->parent_id;
                 $current['name'] = $v->name;
                 if (0 == $v->parent_id){
                 $this->tree[ $v->id ] = &$current;
                 } else {
             $levels[$v->parent_id ]['children'][$v->id] = &$current;
                 }
        }
    }   
    /*
    *App_AbstractModule::preRender overriding
        * @return void
    */
    protected  function preRender()
    {
        $this->_getData();
        }
      /**
       * recursively build html output.
       *
       * @return string
       */
    private function _render($arr)
    {
        $this->output.= '<ul>';
        foreach ($arr as $k=>$v)
        {
            $this->output.= '<li>'.$v['name'].'</li>';
            if( !empty($v['children'])){
                $this->_render($v['children']);
            }
        }
        $this->output.= '</ul>';
        return $this->output;
    }
    /*
    *App_AbstractModule::render overriding
        * @return string
    */
    protected  function render()
    {
            return $this->_render($this->tree);
    }
}