CExpressionDependency
| Package | system.caching.dependencies |
|---|---|
| Inheritance | class CExpressionDependency » CCacheDependency » CComponent |
| Implements | ICacheDependency |
| Since | 1.0 |
| Source Code | framework/caching/dependencies/CExpressionDependency.php |
CExpressionDependency represents a dependency based on the result of a PHP expression.
CExpressionDependency performs dependency checking based on the result of a PHP expression. The dependency is reported as unchanged if and only if the result is the same as the one evaluated when storing the data to cache.
CExpressionDependency performs dependency checking based on the result of a PHP expression. The dependency is reported as unchanged if and only if the result is the same as the one evaluated when storing the data to cache.
Public Properties
| Property | Type | Description | Defined By |
|---|---|---|---|
| dependentData | mixed | the data used to determine if dependency has been changed. | CCacheDependency |
| expression | string | the PHP expression whose result is used to determine the dependency. | CExpressionDependency |
| hasChanged | boolean | whether the dependency has changed. | CCacheDependency |
| reuseDependentData | boolean | Whether this dependency is reusable or not. | CCacheDependency |
Public Methods
| Method | Description | Defined By |
|---|---|---|
| __call() | Calls the named method which is not a class method. | CComponent |
| __construct() | Constructor. | CExpressionDependency |
| __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 |
| 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 |
| evaluateDependency() | Evaluates the dependency by generating and saving the data related with dependency. | CCacheDependency |
| evaluateExpression() | Evaluates a PHP expression or callback under the context of this component. | CComponent |
| getDependentData() | Returns the data used to determine if dependency has been changed. This data is available after evaluateDependency is called. | CCacheDependency |
| getEventHandlers() | Returns the list of attached event handlers for an event. | CComponent |
| getHasChanged() | Returns whether the dependency has changed. | CCacheDependency |
| 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 |
| raiseEvent() | Raises an event. | CComponent |
| resetReusableData() | Resets cached data for reusable dependencies. | CCacheDependency |
Protected Methods
| Method | Description | Defined By |
|---|---|---|
| generateDependentData() | Generates the data needed to determine if dependency has been changed. | CExpressionDependency |
Property Details
expression property
public string $expression;the PHP expression whose result is used to determine the dependency. The expression can also be a valid serializable PHP callback. It will be passed with a parameter which is the dependency object itself.
The PHP expression will be evaluated using evaluateExpression.
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.
Method Details
__construct() method
|
||
| $expression | string | the PHP expression whose result is used to determine the dependency. |
Source Code: framework/caching/dependencies/CExpressionDependency.php#41 (show)
public function __construct($expression='true')
{
$this->expression=$expression;
}Constructor.
generateDependentData() method
|
||
| {return} | mixed | the data needed to determine if dependency has been changed. |
Source Code: framework/caching/dependencies/CExpressionDependency.php#51 (show)
protected function generateDependentData()
{
return $this->evaluateExpression($this->expression);
}Generates the data needed to determine if dependency has been changed. This method returns the result of the PHP expression.
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Licensed under the three clause BSD license.
http://www.yiiframework.com/doc/api/1.1/CExpressionDependency