Class yii\caching\ExpressionDependency

Inheritanceyii\caching\ExpressionDependency » yii\caching\Dependency » yii\base\Object
Implementsyii\base\Configurable
Available since version2.0
Source Code https://github.com/yiisoft/yii2/blob/master/framework/caching/ExpressionDependency.php

ExpressionDependency represents a dependency based on the result of a PHP expression.

ExpressionDependency will use eval() to evaluate the PHP expression. The dependency is reported as unchanged if and only if the result of the expression is the same as the one evaluated when storing the data to cache.

A PHP expression can be any PHP code that has a value. To learn more about what an expression is, please refer to the php manual.

For more details and usage information on Cache, see the guide article on caching.

Public Properties

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PropertyTypeDescriptionDefined By
$data mixed The dependency data that is saved in cache and later is compared with the latest dependency data. yii\caching\Dependency
$expression string The string representation of a PHP expression whose result is used to determine the dependency. yii\caching\ExpressionDependency
$params mixed Custom parameters associated with this dependency. yii\caching\ExpressionDependency
$reusable boolean Whether this dependency is reusable or not. yii\caching\Dependency

Public Methods

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MethodDescriptionDefined By
__call() Calls the named method which is not a class method. yii\base\Object
__construct() Constructor. yii\base\Object
__get() Returns the value of an object property. yii\base\Object
__isset() Checks if a property is set, i.e. defined and not null. yii\base\Object
__set() Sets value of an object property. yii\base\Object
__unset() Sets an object property to null. yii\base\Object
canGetProperty() Returns a value indicating whether a property can be read. yii\base\Object
canSetProperty() Returns a value indicating whether a property can be set. yii\base\Object
className() Returns the fully qualified name of this class. yii\base\Object
evaluateDependency() Evaluates the dependency by generating and saving the data related with dependency. yii\caching\Dependency
getHasChanged() Returns a value indicating whether the dependency has changed. yii\caching\Dependency
hasMethod() Returns a value indicating whether a method is defined. yii\base\Object
hasProperty() Returns a value indicating whether a property is defined. yii\base\Object
init() Initializes the object. yii\base\Object
isChanged() Checks whether the dependency is changed yii\caching\Dependency
resetReusableData() Resets all cached data for reusable dependencies. yii\caching\Dependency

Protected Methods

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MethodDescriptionDefined By
generateDependencyData() Generates the data needed to determine if dependency has been changed. yii\caching\ExpressionDependency
generateReusableHash() Generates a unique hash that can be used for retrieving reusable dependency data. yii\caching\Dependency

Property Details

$expression public property

The string representation of a PHP expression whose result is used to determine the dependency. A PHP expression can be any PHP code that evaluates to a value. To learn more about what an expression is, please refer to the php manual.

public string $expression 'true'
$params public property

Custom parameters associated with this dependency. You may get the value of this property in $expression using $this->params.

public mixed $params null

Method Details

generateDependencyData() protected method

Generates the data needed to determine if dependency has been changed.

This method returns the result of the PHP expression.

protected mixed generateDependencyData ( $cache )
$cache yii\caching\CacheInterface

The cache component that is currently evaluating this dependency

return mixed

The data needed to determine if dependency has been changed.