Controller
extends Component
in package
implements
ViewContextInterface
Controller is the base class for classes containing controller logic.
For more details and usage information on Controller, see the guide article on controllers.
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Table of Contents
Interfaces
- ViewContextInterface
- ViewContextInterface is the interface that should implemented by classes who want to support relative view names.
Constants
- EVENT_AFTER_ACTION = 'afterAction'
- EVENT_BEFORE_ACTION = 'beforeAction'
Properties
- $action : Action|null
- $behaviors : array<string|int, Behavior>
- $defaultAction : string
- $id : string
- $layout : string|null|false
- $module : Module
- $modules : array<string|int, Module>
- $request : Request|array<string|int, mixed>|string
- $response : Response|array<string|int, mixed>|string
- $route : string
- $uniqueId : string
- $view : View|View
- $viewPath : string
- $_behaviors : array<string|int, Behavior>|null
- $_events : array<string|int, mixed>
- $_eventWildcards : array<string|int, mixed>
- $_view : View|null
- $_viewPath : string|null
Methods
- __call() : mixed
- Calls the named method which is not a class method.
- __clone() : mixed
- This method is called after the object is created by cloning an existing one.
- __construct() : mixed
- Constructor.
- __get() : mixed
- Returns the value of a component property.
- __isset() : bool
- Checks if a property is set, i.e. defined and not null.
- __set() : mixed
- Sets the value of a component property.
- __unset() : mixed
- Sets a component property to be null.
- actions() : array<string|int, mixed>
- Declares external actions for the controller.
- afterAction() : mixed
- This method is invoked right after an action is executed.
- attachBehavior() : Behavior
- Attaches a behavior to this component.
- attachBehaviors() : mixed
- Attaches a list of behaviors to the component.
- beforeAction() : bool
- This method is invoked right before an action is executed.
- behaviors() : array<string|int, mixed>
- Returns a list of behaviors that this component should behave as.
- bindActionParams() : array<string|int, mixed>
- Binds the parameters to the action.
- canGetProperty() : bool
- Returns a value indicating whether a property can be read.
- canSetProperty() : bool
- Returns a value indicating whether a property can be set.
- className() : string
- Returns the fully qualified name of this class.
- createAction() : Action|null
- Creates an action based on the given action ID.
- detachBehavior() : Behavior|null
- Detaches a behavior from the component.
- detachBehaviors() : mixed
- Detaches all behaviors from the component.
- ensureBehaviors() : mixed
- Makes sure that the behaviors declared in [[behaviors()]] are attached to this component.
- findLayoutFile() : string|bool
- Finds the applicable layout file.
- getBehavior() : Behavior|null
- Returns the named behavior object.
- getBehaviors() : array<string|int, Behavior>
- Returns all behaviors attached to this component.
- getModules() : array<string|int, Module>
- Returns all ancestor modules of this controller.
- getRoute() : string
- Returns the route of the current request.
- getUniqueId() : string
- Returns the unique ID of the controller.
- getView() : View|View
- Returns the view object that can be used to render views or view files.
- getViewPath() : string
- Returns the directory containing view files for this controller.
- hasEventHandlers() : bool
- Returns a value indicating whether there is any handler attached to the named event.
- hasMethod() : bool
- Returns a value indicating whether a method is defined.
- hasProperty() : bool
- Returns a value indicating whether a property is defined for this component.
- init() : mixed
- Initializes the object.
- off() : bool
- Detaches an existing event handler from this component.
- on() : mixed
- Attaches an event handler to an event.
- render() : string
- Renders a view and applies layout if available.
- renderContent() : string
- Renders a static string by applying a layout.
- renderFile() : string
- Renders a view file.
- renderPartial() : string
- Renders a view without applying layout.
- run() : mixed
- Runs a request specified in terms of a route.
- runAction() : mixed
- Runs an action within this controller with the specified action ID and parameters.
- setView() : mixed
- Sets the view object to be used by this controller.
- setViewPath() : mixed
- Sets the directory that contains the view files.
- trigger() : mixed
- Triggers an event.
- bindInjectedParams() : mixed
- Fills parameters based on types and names in action method signature.
- attachBehaviorInternal() : Behavior
- Attaches a behavior to this component.
Constants
EVENT_AFTER_ACTION
public
mixed
EVENT_AFTER_ACTION
= 'afterAction'
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EVENT_BEFORE_ACTION
public
mixed
EVENT_BEFORE_ACTION
= 'beforeAction'
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Properties
$action
public
Action|null
$action
the action that is currently being executed. This property will be set by [[run()]] when it is called by [[Application]] to run an action.
$behaviors read-only
public
array<string|int, Behavior>
$behaviors
List of behaviors attached to this component.
$defaultAction
public
string
$defaultAction
= 'index'
the ID of the action that is used when the action ID is not specified in the request. Defaults to 'index'.
$id
public
string
$id
the ID of this controller.
$layout
public
string|null|false
$layout
the name of the layout to be applied to this controller's views. This property mainly affects the behavior of [[render()]]. Defaults to null, meaning the actual layout value should inherit that from [[module]]'s layout value. If false, no layout will be applied.
$module
public
Module
$module
the module that this controller belongs to.
$modules read-only
public
array<string|int, Module>
$modules
All ancestor modules that this controller is located within.
$request
public
Request|array<string|int, mixed>|string
$request
= 'request'
The request.
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$response
public
Response|array<string|int, mixed>|string
$response
= 'response'
The response.
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$route read-only
public
string
$route
The route (module ID, controller ID and action ID) of the current request.
$uniqueId read-only
public
string
$uniqueId
The controller ID that is prefixed with the module ID (if any).
$view
public
View|View
$view
The view object that can be used to render views or view files.
$viewPath
public
string
$viewPath
The directory containing the view files for this controller.
$_behaviors
private
array<string|int, Behavior>|null
$_behaviors
the attached behaviors (behavior name => behavior). This is null
when not initialized.
$_events
private
array<string|int, mixed>
$_events
= []
the attached event handlers (event name => handlers)
$_eventWildcards
private
array<string|int, mixed>
$_eventWildcards
= []
the event handlers attached for wildcard patterns (event name wildcard => handlers)
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$_view
private
View|null
$_view
the view object that can be used to render views or view files.
$_viewPath
private
string|null
$_viewPath
the root directory that contains view files for this controller.
Methods
__call()
Calls the named method which is not a class method.
public
__call(string $name, array<string|int, mixed> $params) : mixed
This method will check if any attached behavior has the named method and will execute it if available.
Do not call this method directly as it is a PHP magic method that will be implicitly called when an unknown method is being invoked.
Parameters
- $name : string
-
the method name
- $params : array<string|int, mixed>
-
method parameters
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Return values
mixed —the method return value
__clone()
This method is called after the object is created by cloning an existing one.
public
__clone() : mixed
It removes all behaviors because they are attached to the old object.
__construct()
Constructor.
public
__construct(string $id, Module $module[, array<string|int, mixed> $config = [] ]) : mixed
Parameters
- $id : string
-
the ID of this controller.
- $module : Module
-
the module that this controller belongs to.
- $config : array<string|int, mixed> = []
-
name-value pairs that will be used to initialize the object properties.
__get()
Returns the value of a component property.
public
__get(string $name) : mixed
This method will check in the following order and act accordingly:
- a property defined by a getter: return the getter result
- a property of a behavior: return the behavior property value
Do not call this method directly as it is a PHP magic method that
will be implicitly called when executing $value = $component->property;
.
Parameters
- $name : string
-
the property name
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Return values
mixed —the property value or the value of a behavior's property
__isset()
Checks if a property is set, i.e. defined and not null.
public
__isset(string $name) : bool
This method will check in the following order and act accordingly:
- a property defined by a setter: return whether the property is set
- a property of a behavior: return whether the property is set
- return
false
for non existing properties
Do not call this method directly as it is a PHP magic method that
will be implicitly called when executing isset($component->property)
.
Parameters
- $name : string
-
the property name or the event name
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Return values
bool —whether the named property is set
__set()
Sets the value of a component property.
public
__set(string $name, mixed $value) : mixed
This method will check in the following order and act accordingly:
- a property defined by a setter: set the property value
- an event in the format of "on xyz": attach the handler to the event "xyz"
- a behavior in the format of "as xyz": attach the behavior named as "xyz"
- a property of a behavior: set the behavior property value
Do not call this method directly as it is a PHP magic method that
will be implicitly called when executing $component->property = $value;
.
Parameters
- $name : string
-
the property name or the event name
- $value : mixed
-
the property value
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__unset()
Sets a component property to be null.
public
__unset(string $name) : mixed
This method will check in the following order and act accordingly:
- a property defined by a setter: set the property value to be null
- a property of a behavior: set the property value to be null
Do not call this method directly as it is a PHP magic method that
will be implicitly called when executing unset($component->property)
.
Parameters
- $name : string
-
the property name
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actions()
Declares external actions for the controller.
public
actions() : array<string|int, mixed>
This method is meant to be overwritten to declare external actions for the controller. It should return an array, with array keys being action IDs, and array values the corresponding action class names or action configuration arrays. For example,
return [
'action1' => 'app\components\Action1',
'action2' => [
'class' => 'app\components\Action2',
'property1' => 'value1',
'property2' => 'value2',
],
];
[[\Yii::createObject()]] will be used later to create the requested action using the configuration provided here.
Return values
array<string|int, mixed>afterAction()
This method is invoked right after an action is executed.
public
afterAction(Action $action, mixed $result) : mixed
The method will trigger the [[EVENT_AFTER_ACTION]] event. The return value of the method will be used as the action return value.
If you override this method, your code should look like the following:
public function afterAction($action, $result)
{
$result = parent::afterAction($action, $result);
// your custom code here
return $result;
}
Parameters
- $action : Action
-
the action just executed.
- $result : mixed
-
the action return result.
Return values
mixed —the processed action result.
attachBehavior()
Attaches a behavior to this component.
public
attachBehavior(string $name, string|array<string|int, mixed>|Behavior $behavior) : Behavior
This method will create the behavior object based on the given configuration. After that, the behavior object will be attached to this component by calling the [[Behavior::attach()]] method.
Parameters
- $name : string
-
the name of the behavior.
- $behavior : string|array<string|int, mixed>|Behavior
-
the behavior configuration. This can be one of the following:
- a [[Behavior]] object
- a string specifying the behavior class
- an object configuration array that will be passed to [[Yii::createObject()]] to create the behavior object.
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Return values
Behavior —the behavior object
attachBehaviors()
Attaches a list of behaviors to the component.
public
attachBehaviors(array<string|int, mixed> $behaviors) : mixed
Each behavior is indexed by its name and should be a [[Behavior]] object, a string specifying the behavior class, or an configuration array for creating the behavior.
Parameters
- $behaviors : array<string|int, mixed>
-
list of behaviors to be attached to the component
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beforeAction()
This method is invoked right before an action is executed.
public
beforeAction(Action $action) : bool
The method will trigger the [[EVENT_BEFORE_ACTION]] event. The return value of the method will determine whether the action should continue to run.
In case the action should not run, the request should be handled inside of the beforeAction
code
by either providing the necessary output or redirecting the request. Otherwise the response will be empty.
If you override this method, your code should look like the following:
public function beforeAction($action)
{
// your custom code here, if you want the code to run before action filters,
// which are triggered on the [[EVENT_BEFORE_ACTION]] event, e.g. PageCache or AccessControl
if (!parent::beforeAction($action)) {
return false;
}
// other custom code here
return true; // or false to not run the action
}
Parameters
- $action : Action
-
the action to be executed.
Return values
bool —whether the action should continue to run.
behaviors()
Returns a list of behaviors that this component should behave as.
public
behaviors() : array<string|int, mixed>
Child classes may override this method to specify the behaviors they want to behave as.
The return value of this method should be an array of behavior objects or configurations indexed by behavior names. A behavior configuration can be either a string specifying the behavior class or an array of the following structure:
'behaviorName' => [
'class' => 'BehaviorClass',
'property1' => 'value1',
'property2' => 'value2',
]
Note that a behavior class must extend from [[Behavior]]. Behaviors can be attached using a name or anonymously. When a name is used as the array key, using this name, the behavior can later be retrieved using [[getBehavior()]] or be detached using [[detachBehavior()]]. Anonymous behaviors can not be retrieved or detached.
Behaviors declared in this method will be attached to the component automatically (on demand).
Return values
array<string|int, mixed> —the behavior configurations.
bindActionParams()
Binds the parameters to the action.
public
bindActionParams(Action $action, array<string|int, mixed> $params) : array<string|int, mixed>
This method is invoked by [[Action]] when it begins to run with the given parameters.
Parameters
- $action : Action
-
the action to be bound with parameters.
- $params : array<string|int, mixed>
-
the parameters to be bound to the action.
Return values
array<string|int, mixed> —the valid parameters that the action can run with.
canGetProperty()
Returns a value indicating whether a property can be read.
public
canGetProperty(string $name[, bool $checkVars = true ][, bool $checkBehaviors = true ]) : bool
A property can be read if:
- the class has a getter method associated with the specified name (in this case, property name is case-insensitive);
- the class has a member variable with the specified name (when
$checkVars
is true); - an attached behavior has a readable property of the given name (when
$checkBehaviors
is true).
Parameters
- $name : string
-
the property name
- $checkVars : bool = true
-
whether to treat member variables as properties
- $checkBehaviors : bool = true
-
whether to treat behaviors' properties as properties of this component
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Return values
bool —whether the property can be read
canSetProperty()
Returns a value indicating whether a property can be set.
public
canSetProperty(string $name[, bool $checkVars = true ][, bool $checkBehaviors = true ]) : bool
A property can be written if:
- the class has a setter method associated with the specified name (in this case, property name is case-insensitive);
- the class has a member variable with the specified name (when
$checkVars
is true); - an attached behavior has a writable property of the given name (when
$checkBehaviors
is true).
Parameters
- $name : string
-
the property name
- $checkVars : bool = true
-
whether to treat member variables as properties
- $checkBehaviors : bool = true
-
whether to treat behaviors' properties as properties of this component
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Return values
bool —whether the property can be written
className()
Returns the fully qualified name of this class.
public
static className() : string
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Return values
string —the fully qualified name of this class.
createAction()
Creates an action based on the given action ID.
public
createAction(string $id) : Action|null
The method first checks if the action ID has been declared in [[actions()]]. If so,
it will use the configuration declared there to create the action object.
If not, it will look for a controller method whose name is in the format of actionXyz
where xyz
is the action ID. If found, an [[InlineAction]] representing that
method will be created and returned.
Parameters
- $id : string
-
the action ID.
Return values
Action|null —the newly created action instance. Null if the ID doesn't resolve into any action.
detachBehavior()
Detaches a behavior from the component.
public
detachBehavior(string $name) : Behavior|null
The behavior's [[Behavior::detach()]] method will be invoked.
Parameters
- $name : string
-
the behavior's name.
Return values
Behavior|null —the detached behavior. Null if the behavior does not exist.
detachBehaviors()
Detaches all behaviors from the component.
public
detachBehaviors() : mixed
ensureBehaviors()
Makes sure that the behaviors declared in [[behaviors()]] are attached to this component.
public
ensureBehaviors() : mixed
findLayoutFile()
Finds the applicable layout file.
public
findLayoutFile(View $view) : string|bool
Parameters
- $view : View
-
the view object to render the layout file.
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Return values
string|bool —the layout file path, or false if layout is not needed. Please refer to [[render()]] on how to specify this parameter.
getBehavior()
Returns the named behavior object.
public
getBehavior(string $name) : Behavior|null
Parameters
- $name : string
-
the behavior name
Return values
Behavior|null —the behavior object, or null if the behavior does not exist
getBehaviors()
Returns all behaviors attached to this component.
public
getBehaviors() : array<string|int, Behavior>
Return values
array<string|int, Behavior> —list of behaviors attached to this component
getModules()
Returns all ancestor modules of this controller.
public
getModules() : array<string|int, Module>
The first module in the array is the outermost one (i.e., the application instance), while the last is the innermost one.
Return values
array<string|int, Module> —all ancestor modules that this controller is located within.
getRoute()
Returns the route of the current request.
public
getRoute() : string
Return values
string —the route (module ID, controller ID and action ID) of the current request.
getUniqueId()
Returns the unique ID of the controller.
public
getUniqueId() : string
Return values
string —the controller ID that is prefixed with the module ID (if any).
getView()
Returns the view object that can be used to render views or view files.
public
getView() : View|View
The [[render()]], [[renderPartial()]] and [[renderFile()]] methods will use this view object to implement the actual view rendering. If not set, it will default to the "view" application component.
Return values
View|View —the view object that can be used to render views or view files.
getViewPath()
Returns the directory containing view files for this controller.
public
getViewPath() : string
The default implementation returns the directory named as controller [[id]] under the [[module]]'s [[viewPath]] directory.
Return values
string —the directory containing the view files for this controller.
hasEventHandlers()
Returns a value indicating whether there is any handler attached to the named event.
public
hasEventHandlers(string $name) : bool
Parameters
- $name : string
-
the event name
Return values
bool —whether there is any handler attached to the event.
hasMethod()
Returns a value indicating whether a method is defined.
public
hasMethod(string $name[, bool $checkBehaviors = true ]) : bool
A method is defined if:
- the class has a method with the specified name
- an attached behavior has a method with the given name (when
$checkBehaviors
is true).
Parameters
- $name : string
-
the property name
- $checkBehaviors : bool = true
-
whether to treat behaviors' methods as methods of this component
Return values
bool —whether the method is defined
hasProperty()
Returns a value indicating whether a property is defined for this component.
public
hasProperty(string $name[, bool $checkVars = true ][, bool $checkBehaviors = true ]) : bool
A property is defined if:
- the class has a getter or setter method associated with the specified name (in this case, property name is case-insensitive);
- the class has a member variable with the specified name (when
$checkVars
is true); - an attached behavior has a property of the given name (when
$checkBehaviors
is true).
Parameters
- $name : string
-
the property name
- $checkVars : bool = true
-
whether to treat member variables as properties
- $checkBehaviors : bool = true
-
whether to treat behaviors' properties as properties of this component
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Return values
bool —whether the property is defined
init()
Initializes the object.
public
init() : mixed
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off()
Detaches an existing event handler from this component.
public
off(string $name[, callable|null $handler = null ]) : bool
This method is the opposite of [[on()]].
Note: in case wildcard pattern is passed for event name, only the handlers registered with this wildcard will be removed, while handlers registered with plain names matching this wildcard will remain.
Parameters
- $name : string
-
event name
- $handler : callable|null = null
-
the event handler to be removed. If it is null, all handlers attached to the named event will be removed.
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Return values
bool —if a handler is found and detached
on()
Attaches an event handler to an event.
public
on(string $name, callable $handler[, mixed $data = null ][, bool $append = true ]) : mixed
The event handler must be a valid PHP callback. The following are some examples:
function ($event) { ... } // anonymous function
[$object, 'handleClick'] // $object->handleClick()
['Page', 'handleClick'] // Page::handleClick()
'handleClick' // global function handleClick()
The event handler must be defined with the following signature,
function ($event)
where $event
is an [[Event]] object which includes parameters associated with the event.
Since 2.0.14 you can specify event name as a wildcard pattern:
$component->on('event.group.*', function ($event) {
Yii::trace($event->name . ' is triggered.');
});
Parameters
- $name : string
-
the event name
- $handler : callable
-
the event handler
- $data : mixed = null
-
the data to be passed to the event handler when the event is triggered. When the event handler is invoked, this data can be accessed via [[Event::data]].
- $append : bool = true
-
whether to append new event handler to the end of the existing handler list. If false, the new handler will be inserted at the beginning of the existing handler list.
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render()
Renders a view and applies layout if available.
public
render(string $view[, array<string|int, mixed> $params = [] ]) : string
The view to be rendered can be specified in one of the following formats:
- path alias (e.g. "@app/views/site/index");
- absolute path within application (e.g. "//site/index"): the view name starts with double slashes. The actual view file will be looked for under the [[Application::viewPath|view path]] of the application.
- absolute path within module (e.g. "/site/index"): the view name starts with a single slash. The actual view file will be looked for under the [[Module::viewPath|view path]] of [[module]].
- relative path (e.g. "index"): the actual view file will be looked for under [[viewPath]].
To determine which layout should be applied, the following two steps are conducted:
- In the first step, it determines the layout name and the context module:
- If [[layout]] is specified as a string, use it as the layout name and [[module]] as the context module;
- If [[layout]] is null, search through all ancestor modules of this controller and find the first module whose [[Module::layout|layout]] is not null. The layout and the corresponding module are used as the layout name and the context module, respectively. If such a module is not found or the corresponding layout is not a string, it will return false, meaning no applicable layout.
- In the second step, it determines the actual layout file according to the previously found layout name and context module. The layout name can be:
- a path alias (e.g. "@app/views/layouts/main");
- an absolute path (e.g. "/main"): the layout name starts with a slash. The actual layout file will be looked for under the [[Application::layoutPath|layout path]] of the application;
- a relative path (e.g. "main"): the actual layout file will be looked for under the [[Module::layoutPath|layout path]] of the context module.
If the layout name does not contain a file extension, it will use the default one .php
.
Parameters
- $view : string
-
the view name.
- $params : array<string|int, mixed> = []
-
the parameters (name-value pairs) that should be made available in the view. These parameters will not be available in the layout.
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Return values
string —the rendering result.
renderContent()
Renders a static string by applying a layout.
public
renderContent(string $content) : string
Parameters
- $content : string
-
the static string being rendered
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Return values
string —the rendering result of the layout with the given static string as the $content
variable.
If the layout is disabled, the string will be returned back.
renderFile()
Renders a view file.
public
renderFile(string $file[, array<string|int, mixed> $params = [] ]) : string
Parameters
- $file : string
-
the view file to be rendered. This can be either a file path or a path alias.
- $params : array<string|int, mixed> = []
-
the parameters (name-value pairs) that should be made available in the view.
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Return values
string —the rendering result.
renderPartial()
Renders a view without applying layout.
public
renderPartial(string $view[, array<string|int, mixed> $params = [] ]) : string
This method differs from [[render()]] in that it does not apply any layout.
Parameters
- $view : string
-
the view name. Please refer to [[render()]] on how to specify a view name.
- $params : array<string|int, mixed> = []
-
the parameters (name-value pairs) that should be made available in the view.
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Return values
string —the rendering result.
run()
Runs a request specified in terms of a route.
public
run(string $route[, array<string|int, mixed> $params = [] ]) : mixed
The route can be either an ID of an action within this controller or a complete route consisting of module IDs, controller ID and action ID. If the route starts with a slash '/', the parsing of the route will start from the application; otherwise, it will start from the parent module of this controller.
Parameters
- $route : string
-
the route to be handled, e.g., 'view', 'comment/view', '/admin/comment/view'.
- $params : array<string|int, mixed> = []
-
the parameters to be passed to the action.
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Return values
mixed —the result of the action.
runAction()
Runs an action within this controller with the specified action ID and parameters.
public
runAction(string $id[, array<string|int, mixed> $params = [] ]) : mixed
If the action ID is empty, the method will use [[defaultAction]].
Parameters
- $id : string
-
the ID of the action to be executed.
- $params : array<string|int, mixed> = []
-
the parameters (name-value pairs) to be passed to the action.
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Return values
mixed —the result of the action.
setView()
Sets the view object to be used by this controller.
public
setView(View|View $view) : mixed
Parameters
setViewPath()
Sets the directory that contains the view files.
public
setViewPath(string $path) : mixed
Parameters
- $path : string
-
the root directory of view files.
Tags
trigger()
Triggers an event.
public
trigger(string $name[, Event|null $event = null ]) : mixed
This method represents the happening of an event. It invokes all attached handlers for the event including class-level handlers.
Parameters
- $name : string
-
the event name
- $event : Event|null = null
-
the event instance. If not set, a default [[Event]] object will be created.
bindInjectedParams()
Fills parameters based on types and names in action method signature.
protected
final bindInjectedParams(ReflectionType $type, string $name, array<string|int, mixed> &$args, array<string|int, mixed> &$requestedParams) : mixed
Parameters
- $type : ReflectionType
-
The reflected type of the action parameter.
- $name : string
-
The name of the parameter.
- $args : array<string|int, mixed>
-
The array of arguments for the action, this function may append items to it.
- $requestedParams : array<string|int, mixed>
-
The array with requested params, this function may write specific keys to it.
Tags
attachBehaviorInternal()
Attaches a behavior to this component.
private
attachBehaviorInternal(string|int $name, string|array<string|int, mixed>|Behavior $behavior) : Behavior
Parameters
- $name : string|int
-
the name of the behavior. If this is an integer, it means the behavior is an anonymous one. Otherwise, the behavior is a named one and any existing behavior with the same name will be detached first.
- $behavior : string|array<string|int, mixed>|Behavior
-
the behavior to be attached
Return values
Behavior —the attached behavior.