PHP Array Tree

arrayTree.php
<?php

class Tree { 

  /** 
  * @desc array with elements 
  * @type array 
  * @access private 
  **/ 
  var $aElements; 

  /** 
  * @desc backbone array 
  * @type array 
  * @access private 
  **/ 
  var $result; 
  
  /**
   * Register the levels, to calculate the max level for example
   *
   * @var array
   */
  
  var $levels;  
  
  /**
   * The elements ordered by level
   *
   * @type array
   */
  
  var $lElements;
  
  
	/** 
	* @desc constructor method 
	* @param 
	* @access public 
	* @return void 
	**/
	function Tree(){ 
		$this->aElements  = array(); 
		$this->lElements  = array(); 
		$this->result     = array(); 
		$this->levels 	  = array();
	} 

	/**
	 * Add an element to the array
	 *
	 * @param numeric $iId (The id of the element)
	 * @param array $properties	(All kind of extra properties)
	 * @param numeric $iParentId (The parent id)
	**/


	function addNode($iId, $properties, $iParentId = 0){ 
		$this->aElements[$iId] = array('properties' => $properties, 'parent' => $iParentId); 
	} 

	/**
	 * Gets the parens ids
	 *
	 * @param string/numeric $iId
	**/
	
	function getParents($iId){
		$dad = $this->aElements[$iId]['parent'];
		$parent[] = $dad;
		while($dad){
			if($dad = $this->getParent($dad)){
				$parent[] = $dad;
			}			
		}
		$this->aElements[$iId]['parents'] = $parent;
		return $parent;
	}

	/**
	 * Get the parent ID
	 *
	 * @param string/numeric $iId
	 * @return The parent ID or false
	**/
	
	function getParent($iId){
		if(!empty($this->aElements[$iId]['parent'])){
			return $this->aElements[$iId]['parent'];
		}else{
			return false;
		}
	}
	
	/**
	 * Counts the level depth
	 *
	 * @param string/numeric $iId
	 * @return numeric 
	**/
	
	function level($iId){
		$level = count($this->getParents($iId));
		$this->aElements[$iId]['level'] = $level;
		$this->levels[$iId] = $level;
		if(!$this->getParent($iId)){
			$this->lElements[1][$iId] = $this->aElements[$iId];
		}else{
			$this->lElements[$level+1][$iId] = $this->aElements[$iId];
		}
		return $level;
	}
	
	/**
	 * Returns the max level.
	 *
	 * @return number with the max level depth
	**/
	
	function maxLevel(){
		$max = 0;
		foreach($this->levels as $level){
			if($level > $max){
				$max = $level;
			}
		}
		return ($max+1);
	}
	
	/**
	 * Generates the tree Array
	 *
	 * @return array (within the tree array)
	 */
	
	function getArray() { 

		foreach($this->aElements as $iId => $element){
			$this->level($iId);
		}
		
		foreach($this->lElements[1] as $id => $element){
			$this->result[$id] = '';
		}
		
		for($i=$this->maxLevel();$i>=1;$i--){
			if(isset($this->lElements[$i]) and is_array($this->lElements)){
				foreach($this->lElements[$i] as $id => $element){
					$parent = $this->getParent($id);
					if($parent != 0){
						// Als de dochter een parent heeft
						$this->result[$id]['properties'] = $this->aElements[$id]['properties'];
						if(!isset($this->result[$id])){					
							// Als de pagina nog niet bestond
							$this->result[$parent]['childs'][$id]['properties'] = $element['properties'];
						}else{
							// De pagina bestond dus wel al
							$this->result[$parent]['childs'][$id] = $this->result[$id];
						}
						// Overige verwijderen
						unset($this->result[$id]);
					}else{
						$this->result[$id]['properties'] = $this->aElements[$id]['properties'];
					}
				}
			}
		}
		return $this->result; 
	}
	
	function getLElements(){
		return $this->lElements;
	}
}

?>


example.php

<?php

include('arrayTree.php');

$tree = new Tree();
$sql = "SELECT id,titel,parent,menuid FROM paginas ORDER BY menuid";
$res = mysql_query($sql);
while($page = mysql_fetch_assoc($res)){
	$tree->addNode($page['id'],$page,$page['parent']);
}
$paginas = $tree->getArray();

echo '<pre>';
print_r($paginas);
echo '</pre>';

?>

Ik heb ook een voorbeeld class gemaakt waarmee je deze array kunt uitlezen

readTreeArray.php
<?php
	class printArrayTree {
		
		var $buffer;
		var $array;		
		
		function printArrayTree(){
			$this->array = array();
			$this->buffer = '';
		}		
		
		function make_row($array,$level=0){
			foreach($array as $element){			
				$this->buffer .= '<tr><td>'.$element['properties']['id'].'</td>
						<td style="padding-left: '.(15*$level).'px;">'.($level != 0 ? '&rsaquo; ' : '').' '.$element['properties']['titel'].'</td>
					</tr>';

				if(isset($element['childs']) and is_array($element['childs'])){
					$this->make_row($element['childs'],($level+1));				
				}
			}		
		}
				
		function print_table(){
			return '<table width="50%" cellspacing="0">
				<tr>
				<th>ID</th>
				<th>Pagina naam</th>
			</tr>'.$this->buffer.'</table>';
		}
		
	}
?>


En deze gebruik je uiteindelijk dan zo:

<?php

include('arrayTree.php');

$tree = new Tree();
$sql = "SELECT id,titel,parent,menuid FROM paginas ORDER BY menuid";
$res = mysql_query($sql);
while($page = mysql_fetch_assoc($res)){
	$tree->addNode($page['id'],$page,$page['parent']);
}
$paginas = $tree->getArray();

echo '<pre>';
print_r($paginas);
echo '</pre>';

include('readTreeArray.php');

if(count($paginas) >= 1){		
	$table = new printArrayTree;
	$table->make_row($paginas);
	echo $table->print_table();		
}


?>