怎么样:
function recurse($categories, $parent = null, $level = 0)
{
$ret = '<ul>';
foreach($categories as $index => $category)
{
if($category['root'] == $parent)
{
$ret .= '<li><a href="#"><p class="Tier' . $level . '">' . $category['name'] . '</p></a>';
$ret .= $this->recurse($categories, $category['id'], $level+1);
$ret .= '</li>';
}
}
return $ret . '</ul>';
}
此函数要求您首先在数据库中查询可用类别的整个列表,并假设您的根类别的值为null,但是可以根据当前模式的工作方式将该函数更改为接受-1或0。
$categories = { get from database into an multi-dimensional array };
$Tree = $this->recurse($categories);
echo $Tree;
您可以考虑执行以下操作,以防止在父级不存在任何子级时出现任何空的UL:
function recurse($categories, $parent = null, $level = 0)
{
$ret = '<ul>';
foreach($categories as $index => $category)
{
if($category['root'] == $parent)
{
$ret .= '<li><a href="#"><p class="Tier' . $level . '">' . $category['name'] . '</p></a>';
$sub = $this->recurse($categories, $category['id'], $level+1);
if($sub != '<ul></ul>')
$ret .= $sub;
$ret .= '</li>';
}
}
return $ret . '</ul>';
}
但是,最好的解决方案是选择数据以包括一列,该列包含每个类别有多少个子类别。
select Category.*, (select count(distinct c1.id) from Category as c1 where c1.root = Category.id) as ChildCount from Category
您的功能将是:
function recurse($categories, $parent = null, $level = 0)
{
$ret = '<ul>';
foreach($categories as $index => $category)
{
if($category['root'] == $parent)
{
$ret .= '<li><a href="#"><p class="Tier' . $level . '">' . $category['name'] . '</p></a>';
if($category['ChildCount'] > 0)
$ret .= $this->recurse($categories, $category['id'], $level+1);
$ret .= '</li>';
}
}
return $ret . '</ul>';
}
希望有帮助吗?