* @link http://www.yiiframework.com/ * @copyright 2008-2013 Yii Software LLC * @license http://www.yiiframework.com/license/ */ /** * CList implements an integer-indexed collection class. * * You can access, append, insert, remove an item by using * {@link itemAt}, {@link add}, {@link insertAt}, {@link remove}, and {@link removeAt}. * To get the number of the items in the list, use {@link getCount}. * CList can also be used like a regular array as follows, *
 * $list[]=$item;  // append at the end
 * $list[$index]=$item; // $index must be between 0 and $list->Count
 * unset($list[$index]); // remove the item at $index
 * if(isset($list[$index])) // if the list has an item at $index
 * foreach($list as $index=>$item) // traverse each item in the list
 * $n=count($list); // returns the number of items in the list
 * 
* * To extend CList by doing additional operations with each addition or removal * operation (e.g. performing type check), override {@link insertAt()}, and {@link removeAt()}. * * @property boolean $readOnly Whether this list is read-only or not. Defaults to false. * @property Iterator $iterator An iterator for traversing the items in the list. * @property integer $count The number of items in the list. * * @author Qiang Xue * @package system.collections * @since 1.0 */ class CList extends CComponent implements IteratorAggregate,ArrayAccess,Countable { /** * @var array internal data storage */ private $_d=array(); /** * @var integer number of items */ private $_c=0; /** * @var boolean whether this list is read-only */ private $_r=false; /** * Constructor. * Initializes the list with an array or an iterable object. * @param array $data the initial data. Default is null, meaning no initialization. * @param boolean $readOnly whether the list is read-only * @throws CException If data is not null and neither an array nor an iterator. */ public function __construct($data=null,$readOnly=false) { if($data!==null) $this->copyFrom($data); $this->setReadOnly($readOnly); } /** * @return boolean whether this list is read-only or not. Defaults to false. */ public function getReadOnly() { return $this->_r; } /** * @param boolean $value whether this list is read-only or not */ protected function setReadOnly($value) { $this->_r=$value; } /** * Returns an iterator for traversing the items in the list. * This method is required by the interface IteratorAggregate. * @return Iterator an iterator for traversing the items in the list. */ public function getIterator() { return new CListIterator($this->_d); } /** * Returns the number of items in the list. * This method is required by Countable interface. * @return integer number of items in the list. */ public function count() { return $this->getCount(); } /** * Returns the number of items in the list. * @return integer the number of items in the list */ public function getCount() { return $this->_c; } /** * Returns the item at the specified offset. * This method is exactly the same as {@link offsetGet}. * @param integer $index the index of the item * @return mixed the item at the index * @throws CException if the index is out of the range */ public function itemAt($index) { if(isset($this->_d[$index])) return $this->_d[$index]; elseif($index>=0 && $index<$this->_c) // in case the value is null return $this->_d[$index]; else throw new CException(Yii::t('yii','List index "{index}" is out of bound.', array('{index}'=>$index))); } /** * Appends an item at the end of the list. * @param mixed $item new item * @return integer the zero-based index at which the item is added */ public function add($item) { $this->insertAt($this->_c,$item); return $this->_c-1; } /** * Inserts an item at the specified position. * Original item at the position and the next items * will be moved one step towards the end. * @param integer $index the specified position. * @param mixed $item new item * @throws CException If the index specified exceeds the bound or the list is read-only */ public function insertAt($index,$item) { if(!$this->_r) { if($index===$this->_c) $this->_d[$this->_c++]=$item; elseif($index>=0 && $index<$this->_c) { array_splice($this->_d,$index,0,array($item)); $this->_c++; } else throw new CException(Yii::t('yii','List index "{index}" is out of bound.', array('{index}'=>$index))); } else throw new CException(Yii::t('yii','The list is read only.')); } /** * Removes an item from the list. * The list will first search for the item. * The first item found will be removed from the list. * @param mixed $item the item to be removed. * @return integer the index at which the item is being removed * @throws CException If the item does not exist */ public function remove($item) { if(($index=$this->indexOf($item))>=0) { $this->removeAt($index); return $index; } else return false; } /** * Removes an item at the specified position. * @param integer $index the index of the item to be removed. * @return mixed the removed item. * @throws CException If the index specified exceeds the bound or the list is read-only */ public function removeAt($index) { if(!$this->_r) { if($index>=0 && $index<$this->_c) { $this->_c--; if($index===$this->_c) return array_pop($this->_d); else { $item=$this->_d[$index]; array_splice($this->_d,$index,1); return $item; } } else throw new CException(Yii::t('yii','List index "{index}" is out of bound.', array('{index}'=>$index))); } else throw new CException(Yii::t('yii','The list is read only.')); } /** * Removes all items in the list. */ public function clear() { for($i=$this->_c-1;$i>=0;--$i) $this->removeAt($i); } /** * @param mixed $item the item * @return boolean whether the list contains the item */ public function contains($item) { return $this->indexOf($item)>=0; } /** * @param mixed $item the item * @return integer the index of the item in the list (0 based), -1 if not found. */ public function indexOf($item) { if(($index=array_search($item,$this->_d,true))!==false) return $index; else return -1; } /** * @return array the list of items in array */ public function toArray() { return $this->_d; } /** * Copies iterable data into the list. * Note, existing data in the list will be cleared first. * @param mixed $data the data to be copied from, must be an array or object implementing Traversable * @throws CException If data is neither an array nor a Traversable. */ public function copyFrom($data) { if(is_array($data) || ($data instanceof Traversable)) { if($this->_c>0) $this->clear(); if($data instanceof CList) $data=$data->_d; foreach($data as $item) $this->add($item); } elseif($data!==null) throw new CException(Yii::t('yii','List data must be an array or an object implementing Traversable.')); } /** * Merges iterable data into the map. * New data will be appended to the end of the existing data. * @param mixed $data the data to be merged with, must be an array or object implementing Traversable * @throws CException If data is neither an array nor an iterator. */ public function mergeWith($data) { if(is_array($data) || ($data instanceof Traversable)) { if($data instanceof CList) $data=$data->_d; foreach($data as $item) $this->add($item); } elseif($data!==null) throw new CException(Yii::t('yii','List data must be an array or an object implementing Traversable.')); } /** * Returns whether there is an item at the specified offset. * This method is required by the interface ArrayAccess. * @param integer $offset the offset to check on * @return boolean */ public function offsetExists($offset) { return ($offset>=0 && $offset<$this->_c); } /** * Returns the item at the specified offset. * This method is required by the interface ArrayAccess. * @param integer $offset the offset to retrieve item. * @return mixed the item at the offset * @throws CException if the offset is invalid */ public function offsetGet($offset) { return $this->itemAt($offset); } /** * Sets the item at the specified offset. * This method is required by the interface ArrayAccess. * @param integer $offset the offset to set item * @param mixed $item the item value */ public function offsetSet($offset,$item) { if($offset===null || $offset===$this->_c) $this->insertAt($this->_c,$item); else { $this->removeAt($offset); $this->insertAt($offset,$item); } } /** * Unsets the item at the specified offset. * This method is required by the interface ArrayAccess. * @param integer $offset the offset to unset item */ public function offsetUnset($offset) { $this->removeAt($offset); } }