从数组构建递归嵌套菜单 [英] Build recursive nested menu from array

问题描述

我正在尝试构建一个递归菜单，完成后看起来像这样，带有无限数量的嵌套项目:

I'm trying to build a recursive menu which would look something like this when finished, with an infinite amount of nested items:

Homepage
Services
  Members
  Brokers
  Insurers
Products

我的数据通过表中的简单parent_id列链接在一​​起.

My data is being linked together by a simple parent_id column in my table.

我目前设法抓取了表格中的所有页面，并根据它们的parent_id将它们添加到数组中(见下文).

I have currently managed to grab all the pages in the table and add them into an array based on their parent_id (see below).

Array
(
    [0] => 0-0-1 0-1-2 0-2-12 0-3-27 0-4-28 0-5-29 0-6-30 0-7-31 0-8-33 
    [2] => 2-0-3 2-0-6 2-0-7 2-0-8 
    [3] => 3-0-4 3-0-5 
    [8] => 8-0-9 8-0-10 
    [12] => 12-0-13 12-0-20 
    [13] => 13-0-14 13-1-15 13-2-17 13-3-16 13-4-19 13-5-18 13-9-34 
    [20] => 20-0-21 20-1-22 20-2-24 20-3-23 20-4-26 20-5-25 20-6-11 
)

它的格式为[parent_id] => parent_id-sort_order-id parent_id-sort_order-id，依此类推.

This is formatted as [parent_id] => parent_id-sort_order-id parent_id-sort_order-id and so on.

到目前为止，我的代码如下:

My code so far is as follows:

$sqlGetDropdownPages = "SELECT * FROM `cms_staticPages` ORDER BY `sortOrder` ASC";
$qryGetDropdownPages = mysql_query($sqlGetDropdownPages) or die(mysql_error());
$resGetDropdownPages = mysql_fetch_assoc($qryGetDropdownPages);
$totGetDropdownPages = mysql_num_rows($qryGetDropdownPages);

do {    

    $pageArray[$resGetDropdownPages['parent_id']] .= $resGetDropdownPages['parent_id'].'-'.$resGetDropdownPages['sortOrder'].'-'.$resGetDropdownPages['id'].' ';

} while($resGetDropdownPages = mysql_fetch_assoc($qryGetDropdownPages));

ksort($pageArray);

foreach($pageArray as $i => $value) {

    $explodePages = explode(' ',$value);

    foreach(array_filter($explodePages) as $i2 => $page) {

        $pageInfoExplode = explode('-',$page);

        $getPageInfo = mysql_fetch_assoc(mysql_query("SELECT * FROM `cms_staticPages` WHERE `id` = '".$pageInfoExplode[2]."'"));

        echo $getPageInfo['identifier'].'<br />';

    }

}

这时碰上一堵砖墙，不知道下一步该怎么做.

Ran into a brick wall at this point and can't figure out what to do next.

我尽力解释了这一点，所以是否需要澄清就问一下.

I tried to explain this as well as I possibly can so if any clarification is needed just ask.

如何实现?

推荐答案

我将首先按ID为所有菜单项(页面)建立索引.在第二个循环中，将菜单项与其父母相关联，并跟踪顶级项.

I would index all the menu items (pages) by id first. In the second loop associate menu items with their parents and keep track of top level items.

我会做的一种方法(Render方法只是一个例子):

One of the ways I would do it (Render method is just an example):

$sqlGetDropdownPages = "SELECT * FROM `cms_staticPages` ORDER BY `sortOrder` ASC";
$qryGetDropdownPages = mysql_query($sqlGetDropdownPages) or die(mysql_error());

//indexing pages by id
while ($pageRow = mysql_fetch_assoc($qryGetDropdownPages)) {
    $menuItems[$pageRow['id']] = new MenuItem($pageRow);
}

//associating pages with parents
foreach ($menuItems as $menuItem) {
    if ($menuItem->hasParent()) {
        $menuItem->addToParent($menuItems);
    } else {
        $topLevel[] = $menuItem;
    }
}

//$topLevel is an array of menuItems without parents
$render = '<ul>';
foreach ($topLevel as $menuItem) {
    $render .= $menuItem->render(true);
}
$render .= '</ul>';

MenuItem类看起来像这样

MenuItem class would look something like this

class MenuItem {

    /**
     * @var array
     */
    private $data;

    /**
     * @var MenuItem[]
     */
    private $children = array();

    /**
     * @var MenuItem
     */
    private $parent;

    /**
     * @param array $data
     */
    public function __construct($data) {
        $this->data = $data;
    }

    /**
     * Finds the parent in the collection and adds itself to it
     * @param MenuItem[] $menuItems
     */
    public function addToParent($menuItems) {
        if (isset($menuItems[$this->data['parent_id']])) {
            $this->parent = $menuItems[$this->data['parent_id']];
            $this->parent->addChild($this);
        }
    }

    /**
     * @return bool
     */
    public function hasParent() {
        return empty($this->data['parent_id']);
    }

    /**
     * @param MenuItem $child
     */
    public function addChild(MenuItem $child) {
        $this->children[] = $child;
    }

    /**
     * Renders the menu with ul li
     * @param bool $withChildren
     * @return string
     */
    public function render($withChildren = false) {
        $render = '<li>' . $this->data['identifier'] . '</li>';

        if ($withChildren) {
            $render .= '<ul>';
            foreach ($this->children as $child) {
                $render .= $child->render(true);
            }
            $render .= '</ul>';
        }

        return $render;
    }

}

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