FilterValidator
extends Validator
in package
FilterValidator converts the attribute value according to a filter.
FilterValidator is actually not a validator but a data processor. It invokes the specified filter callback to process the attribute value and save the processed value back to the attribute. The filter must be a valid PHP callback with the following signature:
function foo($value) {
// compute $newValue here
return $newValue;
}
Many PHP functions qualify this signature (e.g. trim()
).
If the callback function requires non-null argument (important since PHP 8.1)
remember to set [[skipOnEmpty]] to true
otherwise you may trigger an error.
To specify the filter, set [[filter]] property to be the callback.
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Table of Contents
Properties
- $attributeNames : array<string|int, mixed>
- $attributes : array<string|int, mixed>|string
- $behaviors : array<string|int, Behavior>
- $builtInValidators : array<string|int, mixed>
- $enableClientValidation : bool
- $except : array<string|int, mixed>|string
- $filter : callable
- $isEmpty : callable|null
- $message : string|null
- $on : array<string|int, mixed>|string
- $skipOnArray : bool
- $skipOnEmpty : bool
- $skipOnError : bool
- $validationAttributes : array<string|int, mixed>|null
- $when : callable|null
- $whenClient : string|null
- $_behaviors : array<string|int, Behavior>|null
- $_events : array<string|int, mixed>
- $_eventWildcards : array<string|int, mixed>
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.
- addError() : mixed
- Adds an error about the specified attribute to the model object.
- attachBehavior() : Behavior
- Attaches a behavior to this component.
- attachBehaviors() : mixed
- Attaches a list of behaviors to the component.
- behaviors() : array<string|int, mixed>
- Returns a list of behaviors that this component should behave as.
- 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.
- clientValidateAttribute() : string|null
- Returns the JavaScript needed for performing client-side validation.
- createValidator() : Validator
- Creates a validator object.
- 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.
- getAttributeNames() : array<string|int, mixed>
- Returns cleaned attribute names without the `!` character at the beginning.
- getBehavior() : Behavior|null
- Returns the named behavior object.
- getBehaviors() : array<string|int, Behavior>
- Returns all behaviors attached to this component.
- getClientOptions() : array<string|int, mixed>
- Returns the client-side validation options.
- getValidationAttributes() : array<string|int, mixed>|null
- Returns a list of attributes this validator applies to.
- 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.
- isActive() : bool
- Returns a value indicating whether the validator is active for the given scenario and attribute.
- isEmpty() : bool
- Checks if the given value is empty.
- off() : bool
- Detaches an existing event handler from this component.
- on() : mixed
- Attaches an event handler to an event.
- trigger() : mixed
- Triggers an event.
- validate() : bool
- Validates a given value.
- validateAttribute() : mixed
- Validates a single attribute.
- validateAttributes() : mixed
- Validates the specified object.
- formatMessage() : string
- Formats a mesage using the I18N, or simple strtr if `\Yii::$app` is not available.
- validateValue() : array<string|int, mixed>|null
- Validates a value.
- attachBehaviorInternal() : Behavior
- Attaches a behavior to this component.
Properties
$attributeNames read-only
public
array<string|int, mixed>
$attributeNames
Attribute names.
$attributes
public
array<string|int, mixed>|string
$attributes
= []
attributes to be validated by this validator. For multiple attributes, please specify them as an array; for single attribute, you may use either a string or an array.
$behaviors read-only
public
array<string|int, Behavior>
$behaviors
List of behaviors attached to this component.
$builtInValidators
public
static array<string|int, mixed>
$builtInValidators
= ['boolean' => 'yii\validators\BooleanValidator', 'captcha' => 'yii\captcha\CaptchaValidator', 'compare' => 'yii\validators\CompareValidator', 'date' => 'yii\validators\DateValidator', 'datetime' => ['class' => 'yii\validators\DateValidator', 'type' => \yii\validators\DateValidator::TYPE_DATETIME], 'time' => ['class' => 'yii\validators\DateValidator', 'type' => \yii\validators\DateValidator::TYPE_TIME], 'default' => 'yii\validators\DefaultValueValidator', 'double' => 'yii\validators\NumberValidator', 'each' => 'yii\validators\EachValidator', 'email' => 'yii\validators\EmailValidator', 'exist' => 'yii\validators\ExistValidator', 'file' => 'yii\validators\FileValidator', 'filter' => 'yii\validators\FilterValidator', 'image' => 'yii\validators\ImageValidator', 'in' => 'yii\validators\RangeValidator', 'integer' => ['class' => 'yii\validators\NumberValidator', 'integerOnly' => true], 'match' => 'yii\validators\RegularExpressionValidator', 'number' => 'yii\validators\NumberValidator', 'required' => 'yii\validators\RequiredValidator', 'safe' => 'yii\validators\SafeValidator', 'string' => 'yii\validators\StringValidator', 'trim' => ['class' => 'yii\validators\TrimValidator', 'skipOnArray' => true], 'unique' => 'yii\validators\UniqueValidator', 'url' => 'yii\validators\UrlValidator', 'ip' => 'yii\validators\IpValidator']
list of built-in validators (name => class or configuration)
$enableClientValidation
public
bool
$enableClientValidation
= true
whether to enable client-side validation for this validator. The actual client-side validation is done via the JavaScript code returned by [[clientValidateAttribute()]]. If that method returns null, even if this property is true, no client-side validation will be done by this validator.
$except
public
array<string|int, mixed>|string
$except
= []
scenarios that the validator should not be applied to. For multiple scenarios, please specify them as an array; for single scenario, you may use either a string or an array.
$filter
public
callable
$filter
the filter. This can be a global function name, anonymous function, etc. The function signature must be as follows,
function foo($value) {
// compute $newValue here
return $newValue;
}
$isEmpty
public
callable|null
$isEmpty
a PHP callable that replaces the default implementation of [[isEmpty()]].
If not set, [[isEmpty()]] will be used to check if a value is empty. The signature
of the callable should be function ($value)
which returns a boolean indicating
whether the value is empty.
$message
public
string|null
$message
the user-defined error message. It may contain the following placeholders which will be replaced accordingly by the validator:
-
{attribute}
: the label of the attribute being validated -
{value}
: the value of the attribute being validated
Note that some validators may introduce other properties for error messages used when specific validation conditions are not met. Please refer to individual class API documentation for details about these properties. By convention, this property represents the primary error message used when the most important validation condition is not met.
$on
public
array<string|int, mixed>|string
$on
= []
scenarios that the validator can be applied to. For multiple scenarios, please specify them as an array; for single scenario, you may use either a string or an array.
$skipOnArray
public
bool
$skipOnArray
= false
whether the filter should be skipped if an array input is given. If true and an array input is given, the filter will not be applied.
$skipOnEmpty
public
bool
$skipOnEmpty
= false
this property is overwritten to be false so that this validator will be applied when the value being validated is empty.
$skipOnError
public
bool
$skipOnError
= true
whether this validation rule should be skipped if the attribute being validated already has some validation error according to some previous rules. Defaults to true.
$validationAttributes read-only
public
array<string|int, mixed>|null
$validationAttributes
List of attribute names.
$when
public
callable|null
$when
a PHP callable whose return value determines whether this validator should be applied.
The signature of the callable should be function ($model, $attribute)
, where $model
and $attribute
refer to the model and the attribute currently being validated. The callable should return a boolean value.
This property is mainly provided to support conditional validation on the server-side. If this property is not set, this validator will be always applied on the server-side.
The following example will enable the validator only when the country currently selected is USA:
function ($model) {
return $model->country == Country::USA;
}
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$whenClient
public
string|null
$whenClient
a JavaScript function name whose return value determines whether this validator should be applied
on the client-side. The signature of the function should be function (attribute, value)
, where
attribute
is an object describing the attribute being validated (see [[clientValidateAttribute()]])
and value
the current value of the attribute.
This property is mainly provided to support conditional validation on the client-side. If this property is not set, this validator will be always applied on the client-side.
The following example will enable the validator only when the country currently selected is USA:
function (attribute, value) {
return $('#country').val() === 'USA';
}
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$_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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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([array<string|int, mixed> $config = [] ]) : mixed
The default implementation does two things:
- Initializes the object with the given configuration
$config
. - Call [[init()]].
If this method is overridden in a child class, it is recommended that
- the last parameter of the constructor is a configuration array, like
$config
here. - call the parent implementation at the end of the constructor.
Parameters
- $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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addError()
Adds an error about the specified attribute to the model object.
public
addError(Model $model, string $attribute, string $message[, array<string|int, mixed> $params = [] ]) : mixed
This is a helper method that performs message selection and internationalization.
Parameters
- $model : Model
-
the data model being validated
- $attribute : string
-
the attribute being validated
- $message : string
-
the error message
- $params : array<string|int, mixed> = []
-
values for the placeholders in the error message
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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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.
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.
clientValidateAttribute()
Returns the JavaScript needed for performing client-side validation.
public
clientValidateAttribute(mixed $model, mixed $attribute, mixed $view) : string|null
Parameters
- $model : mixed
-
the data model being validated
- $attribute : mixed
-
the name of the attribute to be validated.
- $view : mixed
-
the view object that is going to be used to render views or view files containing a model form with this validator applied.
Return values
string|null —the client-side validation script. Null if the validator does not support client-side validation.
createValidator()
Creates a validator object.
public
static createValidator(string|Closure $type, Model $model, array<string|int, mixed>|string $attributes[, array<string|int, mixed> $params = [] ]) : Validator
Parameters
- $type : string|Closure
-
the validator type. This can be either:
- a built-in validator name listed in [[builtInValidators]];
- a method name of the model class;
- an anonymous function;
- a validator class name.
- $model : Model
-
the data model to be validated.
- $attributes : array<string|int, mixed>|string
-
list of attributes to be validated. This can be either an array of the attribute names or a string of comma-separated attribute names.
- $params : array<string|int, mixed> = []
-
initial values to be applied to the validator properties.
Return values
Validator —the validator
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
getAttributeNames()
Returns cleaned attribute names without the `!` character at the beginning.
public
getAttributeNames() : array<string|int, mixed>
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Return values
array<string|int, mixed> —attribute names.
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
getClientOptions()
Returns the client-side validation options.
public
getClientOptions(mixed $model, mixed $attribute) : array<string|int, mixed>
Parameters
- $model : mixed
-
the model being validated
- $attribute : mixed
-
the attribute name being validated
Return values
array<string|int, mixed> —the client-side validation options
getValidationAttributes()
Returns a list of attributes this validator applies to.
public
getValidationAttributes([array<string|int, mixed>|string|null $attributes = null ]) : array<string|int, mixed>|null
Parameters
- $attributes : array<string|int, mixed>|string|null = null
-
the list of attributes to be validated.
- If this is
null
, the result will be equal to [[getAttributeNames()]]. - If this is a string or an array, the intersection of [[getAttributeNames()]] and the specified attributes will be returned.
- If this is
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Return values
array<string|int, mixed>|null —list of attribute names.
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
isActive()
Returns a value indicating whether the validator is active for the given scenario and attribute.
public
isActive(string $scenario) : bool
A validator is active if
- the validator's
on
property is empty, or - the validator's
on
property contains the specified scenario
Parameters
- $scenario : string
-
scenario name
Return values
bool —whether the validator applies to the specified scenario.
isEmpty()
Checks if the given value is empty.
public
isEmpty(mixed $value) : bool
A value is considered empty if it is null, an empty array, or an empty string. Note that this method is different from PHP empty(). It will return false when the value is 0.
Parameters
- $value : mixed
-
the value to be checked
Return values
bool —whether the value is empty
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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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.
validate()
Validates a given value.
public
validate(mixed $value[, string|null &$error = null ]) : bool
You may use this method to validate a value out of the context of a data model.
Parameters
- $value : mixed
-
the data value to be validated.
- $error : string|null = null
-
the error message to be returned, if the validation fails.
Return values
bool —whether the data is valid.
validateAttribute()
Validates a single attribute.
public
validateAttribute(mixed $model, mixed $attribute) : mixed
Parameters
- $model : mixed
-
the data model to be validated
- $attribute : mixed
-
the name of the attribute to be validated.
validateAttributes()
Validates the specified object.
public
validateAttributes(Model $model[, array<string|int, mixed>|string|null $attributes = null ]) : mixed
Parameters
- $model : Model
-
the data model being validated
- $attributes : array<string|int, mixed>|string|null = null
-
the list of attributes to be validated. Note that if an attribute is not associated with the validator - it will be ignored. If this parameter is null, every attribute listed in [[attributes]] will be validated.
formatMessage()
Formats a mesage using the I18N, or simple strtr if `\Yii::$app` is not available.
protected
formatMessage(string $message, array<string|int, mixed> $params) : string
Parameters
- $message : string
- $params : array<string|int, mixed>
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Return values
stringvalidateValue()
Validates a value.
protected
validateValue(mixed $value) : array<string|int, mixed>|null
A validator class can implement this method to support data validation out of the context of a data model.
Parameters
- $value : mixed
-
the data value to be validated.
Tags
Return values
array<string|int, mixed>|null —the error message and the array of parameters to be inserted into the error message.
if (!$valid) {
return [$this->message, [
'param1' => $this->param1,
'formattedLimit' => Yii::$app->formatter->asShortSize($this->getSizeLimit()),
'mimeTypes' => implode(', ', $this->mimeTypes),
'param4' => 'etc...',
]];
}
return null;
for this example message
template can contain {param1}
, {formattedLimit}
, {mimeTypes}
, {param4}
Null should be returned if the data is valid.
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.