我已经完成了这对于PyroCMS中的页面管理器，但这不是一件容易的任务。

每个页面都有自己的slug和parent_id，然后读取正确的页面，页面子弹和加入孩子。它知道有多少个孩子，所以如果有5个孩子，它选择第5个自联接表。

这里是一个代码示例：

  public function get_by_path（$ segments = array（））
 {
 //如果URI作为字符串传递，爆炸创建一个段数组
 if（is_string（$ segments））
 {
 $ segments = explode（'/'，$ segments）; 
} 

 //计算出多少段
 $ total_segments = count（$ segments）; 

 //这是目标别名（树中的最后一页）
 $ target_alias ='p'。$ total_segments; 

 //开始查询，从目标别名中选择（*）从页面
 $ this-> db-> select（$ target_alias。'。*'）; 
 $ it-> db-> from（'pages p1'）; 

 //循环thorugh each slug 
 $ level = 1; 
 foreach（$ segments as $ segment）
 {
 // Current是当前页面，child是下一个要加入的页面。 
 $ current_alias ='p'。$ level; 
 $ child_alias ='p'。（$ level  -  1）; 

 //我们不想再次加入第一页
 if（$ level！= 1）
 {
 $ this-> db-> join （'pages'。$ current_alias，$ current_alias。'。parent_id ='。$ child_alias。'。id'）; 
} 

 //添加slug到where子句以保持我们在正确的树
 $ this-> db->其中（$ current_alias。'.slug' $ segment）; 

 //增量
 ++ $ level; 
} 

 //只能是一个结果
 $ this-> db-> limit（1）; 

 return $ this-> db-> get（） - > row（）; 
} 
 

这有点坚果，但它工作完美。这可能真的很慢，所以PyroCMS还维护一个查找表，其id和页面URI匹配很快。

你可以在这里看到整个模型： p>

http://github.com/philsturgeon/pyrocms/blob/master/application/modules/core/pages/models/pages_m.php

ok, so i'm very new to codeigniter and from what i have learned by now i can't figure out how can i create a dynamic category -> subcategory -> subsubcategory system. Can you give me some guidelines please...some references, anything to guide me on what should i learn to accomplish that? thanks

i should get my URL like this www.site.com/category/subcategory/subsubcategory/etc... , you know what i mean.

I have done this for the page manager in PyroCMS but it is no easy task.

Each page has its own slug and parent_id, then to read the correct page it loops through each of the page slugs and joins the child. It knows how many children there are so if there are 5 children it selects the 5th self-joined table.

Here is an example of the code:

public function get_by_path($segments = array())
{
 // If the URI has been passed as a string, explode to create an array of segments
 if(is_string($segments))
    {
     $segments = explode('/', $segments);
    }

 // Work out how many segments there are
    $total_segments = count($segments);

// Which is the target alias (the final page in the tree)
    $target_alias = 'p'.$total_segments;

    // Start Query, Select (*) from Target Alias, from Pages
    $this->db->select($target_alias.'.*');
    $this->db->from('pages p1');

    // Loop thorugh each Slug
    $level = 1;
    foreach( $segments as $segment )
    {
        // Current is the current page, child is the next page to join on.
        $current_alias = 'p'.$level;
        $child_alias = 'p'.($level - 1);

        // We dont want to join the first page again
        if($level != 1)
        {
            $this->db->join('pages '.$current_alias, $current_alias.'.parent_id = '.$child_alias.'.id');
        }

        // Add slug to where clause to keep us on the right tree
        $this->db->where($current_alias . '.slug', $segment);

        // Increment
        ++$level;
    }

    // Can only be one result
    $this->db->limit(1);

    return $this->db->get()->row();
}

It's a bit nuts but it works perfectly. This can be really slow so PyroCMS also maintains a look-up table which has id and the page URI to match quickly.

You can see the whole model here:

http://github.com/philsturgeon/pyrocms/blob/master/application/modules/core/pages/models/pages_m.php