本篇文章是对thinkphp的左右值无限分类进行了详细的分析介绍,需要的朋友参考下
以前一直使用父子无限分类,这种分类结构清晰,使用也简单。但若分类数量很大的话,在查询上性能不佳。比如在做导航菜单中,我要根据某一分类查询出整个分类树的话(祖辈)。
复制代码 代码如下:
_id
/**
+----------------------------------------------------------
* 构造函数
* @access public
* @return void
+----------------------------------------------------------
*/
public function __construct($left,$right,$id){
parent::__construct();
$this->_left = $left;
$this->_right = $right;
$this->_id = $id;
}
/**
+----------------------------------------------------------
* 根据node$this->_id得到该node的所有值
* @access public
* @param $nodeId
* @return array
+----------------------------------------------------------
*/
public function getNodeById($nodeId)
{
if($nodeId>0)
{
return $this->getById($nodeId);
}
else
{
throw_exception('未知$this->_id');
return false;
}
}
/**
+----------------------------------------------------------
* 获取父节点,含直属父类(type=1),所有父类:type=0
* @access public
* @param $nodeId int 节点$this->_id
* @return $parentNode array()
+----------------------------------------------------------
*/
public function getParentNode($nodeId,$type = 0)
{
if($nodeId == 0) throw_exception('未知$this->_id');;
$currentNode = $this->getNodeById($nodeId);
if($currentNode)
{
$condition = " ".$this->_left.'<'.$currentNode[$this->_left].' and '.$this->_right.' >'.$currentNode[$this->_right]." ";
if($type ==1) //直属父类
{
return $this->where($condition)->order($this->_left." DESC")->limit(1)->find();
//
$sql = "SELECT * FROM ".TABLE_NAME." WHERE {$condition} ORDER BY ".$this->_left." DESC LIMIT 1";
//
return mysql_query($sql) or die(mysql_error());
}
else if($type ==0)
{
return $this->where($condition)->findAll();
//
$sql = "SELECT * FROM ".TABLE_NAME." WHERE {$condition} ";
//
return mysql_query($sql) or die(mysql_error());
}
}
else
{
return false;
}
}
/**
+----------------------------------------------------------
* 当前节点下子孙节点总数.子孙总数=(当前节点的右值 - 当前节点的左值-1)/2
* @access public
* @param $node_id int 节点$this->_id
* @return $amount int 该节点下的子孙总数
*
+----------------------------------------------------------
*/
public function getChildCount($nodeId)
{
$currentNode = $this->getNodeById($nodeId);
if(!empty($currentNode))
{
return (int)($currentNode[$this->_right]-$currentNode[$this->_left] -1)/2;
}
}
/**
+----------------------------------------------------------
* 获取当前节点下所有子节点。 当 A子类的右节点=B子类左节点-1 则 A、B属于同一级别
* @access public
* @param $curentId
* @param $type int 0:当前节点下所有子类,1为当前节点下一级子类
* @return bool
+----------------------------------------------------------
*/
public function getChild($nodeId,$type=0)
{
$currentNode = $this->getNodeById($nodeId);
if($currentNode[$this->_left]-$currentNode[$this->_right] ==1)
{
return false; //当 该节点左值 - 右值=1 时,其下没有子节点。
}
else
{
$condition = $this->_left.'>'.$currentNode[$this->_left].' and '.$this->_right .'<'.$currentNode[$this->_right];
$child = $this->where($condition)->findAll();
if($type == 0)//所有子类
{
return $child;
}
else if($type ==1) //获取当前节点下一级分类
{
$subArr = array(); //一级子类
foreach ($child as $k=>$sub) {
//子类的左节点=父类左节点+1,则子类为第一个子类
if($sub[$this->_left]==$currentNode[$this->_left]+1)
{
//$right = $sub[$k][$this->_right]; //当前节点的右节点
$firstSub = $sub; //当前节点下第一个子类
array_push($subArr,$firstSub); //子类入栈
unset($child[$k]);
}
}
$rightVal = $firstSub[$this->_right]; //第一个子节点为比较标志
$childCount = count($child);//剩余子节点数
for($i=0;$i<$childCount;$i++) //循环检索出 同级子节点
{
foreach ($child as $key => $sub2) {
if($rightVal == $sub2[$this->_left]-1)
{
$rightVal = $sub2[$this->_right]; //把循环当前的node的右节点当做比较值
array_push($subArr,$sub2);
unset($child[$key]);
}
}
}
return $subArr;
}
}
}
/**
+----------------------------------------------------------
* 返回当前节点的完整路径
* @access public
* @param $nodeId
* @return array
+----------------------------------------------------------
*/
public function getSinglePath($nodeId)
{
$sql = "select parent.* from __TABLE__ as node,__TABLE__ as parent where node.{$this->_left} between parent.{$this->_left}
AND parent.{$this->_right} AND node.{$this->_id} = {$nodeId} order by parent.{$this->_left}";
//
echo $sql;
return $this->query($sql);
}
/**
+----------------------------------------------------------
* 添加子节点,分3种:0:在当前节点下最后追加一个子节点;1:在当前节点下追加第一个子节点;
复制代码 代码如下:
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抢