CStack

Package system.collections
Inheritance class CStack » CComponent
Implements IteratorAggregate, Traversable, Countable
Since 1.0
Source Code framework/collections/CStack.php
CStack implements a stack.

The typical stack operations are implemented, which include push(), pop() and peek(). In addition, contains() can be used to check if an item is contained in the stack. To obtain the number of the items in the stack, check the Count property.

Items in the stack may be traversed using foreach as follows,
foreach($stack as $item) ...

Public Properties

Property Type Description Defined By
count integer Returns the number of items in the stack. CStack
iterator Iterator Returns an iterator for traversing the items in the stack. CStack

Public Methods

Method Description Defined By
__call() Calls the named method which is not a class method. CComponent
__construct() Constructor. CStack
__get() Returns a property value, an event handler list or a behavior based on its name. CComponent
__isset() Checks if a property value is null. CComponent
__set() Sets value of a component property. CComponent
__unset() Sets a component property to be null. CComponent
asa() Returns the named behavior object. CComponent
attachBehavior() Attaches a behavior to this component. CComponent
attachBehaviors() Attaches a list of behaviors to the component. CComponent
attachEventHandler() Attaches an event handler to an event. CComponent
canGetProperty() Determines whether a property can be read. CComponent
canSetProperty() Determines whether a property can be set. CComponent
clear() Removes all items in the stack. CStack
contains() CStack
copyFrom() Copies iterable data into the stack. CStack
count() Returns the number of items in the stack. CStack
detachBehavior() Detaches a behavior from the component. CComponent
detachBehaviors() Detaches all behaviors from the component. CComponent
detachEventHandler() Detaches an existing event handler. CComponent
disableBehavior() Disables an attached behavior. CComponent
disableBehaviors() Disables all behaviors attached to this component. CComponent
enableBehavior() Enables an attached behavior. CComponent
enableBehaviors() Enables all behaviors attached to this component. CComponent
evaluateExpression() Evaluates a PHP expression or callback under the context of this component. CComponent
getCount() Returns the number of items in the stack. CStack
getEventHandlers() Returns the list of attached event handlers for an event. CComponent
getIterator() Returns an iterator for traversing the items in the stack. CStack
hasEvent() Determines whether an event is defined. CComponent
hasEventHandler() Checks whether the named event has attached handlers. CComponent
hasProperty() Determines whether a property is defined. CComponent
peek() Returns the item at the top of the stack. CStack
pop() Pops up the item at the top of the stack. CStack
push() Pushes an item into the stack. CStack
raiseEvent() Raises an event. CComponent
toArray() CStack

Property Details

count property read-only

public integer getCount()

Returns the number of items in the stack.

iterator property read-only

public Iterator getIterator()

Returns an iterator for traversing the items in the stack. This method is required by the interface IteratorAggregate.

Method Details

__construct() method

public void __construct(array $data=NULL)
$data array the initial data. Default is null, meaning no initialization.
Source Code: framework/collections/CStack.php#51 (show)
public function __construct($data=null)
{
    if(
$data!==null)
        
$this->copyFrom($data);
}

Constructor. Initializes the stack with an array or an iterable object.

clear() method

public void clear()
Source Code: framework/collections/CStack.php#89 (show)
public function clear()
{
    
$this->_c=0;
    
$this->_d=array();
}

Removes all items in the stack.

contains() method

public boolean contains(mixed $item)
$item mixed the item
{return} boolean whether the stack contains the item
Source Code: framework/collections/CStack.php#99 (show)
public function contains($item)
{
    return 
array_search($item,$this->_d,true)!==false;
}

copyFrom() method

public void copyFrom(mixed $data)
$data mixed the data to be copied from, must be an array or object implementing Traversable
Source Code: framework/collections/CStack.php#71 (show)
public function copyFrom($data)
{
    if(
is_array($data) || ($data instanceof Traversable))
    {
        
$this->clear();
        foreach(
$data as $item)
        {
            
$this->_d[]=$item;
            ++
$this->_c;
        }
    }
    elseif(
$data!==null)
        throw new 
CException(Yii::t('yii','Stack data must be an array or an object implementing Traversable.'));
}

Copies iterable data into the stack. Note, existing data in the list will be cleared first.

count() method

public integer count()
{return} integer number of items in the stack.
Source Code: framework/collections/CStack.php#168 (show)
public function count()
{
    return 
$this->getCount();
}

Returns the number of items in the stack. This method is required by Countable interface.

getCount() method

public integer getCount()
{return} integer the number of items in the stack
Source Code: framework/collections/CStack.php#158 (show)
public function getCount()
{
    return 
$this->_c;
}

Returns the number of items in the stack.

getIterator() method

public Iterator getIterator()
{return} Iterator an iterator for traversing the items in the stack.
Source Code: framework/collections/CStack.php#149 (show)
public function getIterator()
{
    return new 
CStackIterator($this->_d);
}

Returns an iterator for traversing the items in the stack. This method is required by the interface IteratorAggregate.

peek() method

public mixed peek()
{return} mixed item at the top of the stack
Source Code: framework/collections/CStack.php#110 (show)
public function peek()
{
    if(
$this->_c)
        return 
$this->_d[$this->_c-1];
    else
        throw new 
CException(Yii::t('yii','The stack is empty.'));
}

Returns the item at the top of the stack. Unlike pop(), this method does not remove the item from the stack.

pop() method

public mixed pop()
{return} mixed the item at the top of the stack
Source Code: framework/collections/CStack.php#123 (show)
public function pop()
{
    if(
$this->_c)
    {
        --
$this->_c;
        return 
array_pop($this->_d);
    }
    else
        throw new 
CException(Yii::t('yii','The stack is empty.'));
}

Pops up the item at the top of the stack.

push() method

public void push(mixed $item)
$item mixed the item to be pushed into the stack
Source Code: framework/collections/CStack.php#138 (show)
public function push($item)
{
    ++
$this->_c;
    
$this->_d[]=$item;
}

Pushes an item into the stack.

toArray() method

public array toArray()
{return} array the list of items in stack
Source Code: framework/collections/CStack.php#60 (show)
public function toArray()
{
    return 
$this->_d;
}

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Licensed under the three clause BSD license.
http://www.yiiframework.com/doc/api/1.1/CStack