Class yii\caching\ExpressionDependency
| Inheritance | yii\caching\ExpressionDependency » yii\caching\Dependency » yii\base\Object |
|---|---|
| Implements | yii\base\Configurable |
| Available since version | 2.0 |
| 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
| Property | Type | Description | Defined 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
| Method | Description | Defined 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
| Method | Description | Defined 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
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.
Custom parameters associated with this dependency. You may get the value
of this property in $expression using $this->params.
Method Details
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\Cache | The cache component that is currently evaluating this dependency |
| return | mixed | The data needed to determine if dependency has been changed. |
|---|---|---|