# Model

> Model is the base class for data models.

[API reference](/docs/api/index.md) › [yii](/docs/api/yii/index.md) › [base](/docs/api/yii/base/index.md) › Model

| class | `yii\base\Model` |
| --- | --- |
| Extends | [`Component`](/docs/api/yii/base/component/index.md) » [`BaseObject`](/docs/api/yii/base/baseobject/index.md) |
| Implements | [`StaticInstanceInterface`](/docs/api/yii/base/staticinstanceinterface/index.md), [`IteratorAggregate`](https://www.php.net/manual/en/class.iteratoraggregate.php), [`ArrayAccess`](https://www.php.net/manual/en/class.arrayaccess.php), [`Arrayable`](/docs/api/yii/base/arrayable/index.md), [`Configurable`](/docs/api/yii/base/configurable/index.md) |
| Uses traits | [`ArrayableTrait`](/docs/api/yii/base/arrayabletrait/index.md), [`StaticInstanceTrait`](/docs/api/yii/base/staticinstancetrait/index.md) |
| Since | 2.0 |
| Source | [`framework/base/Model.php`](https://github.com/yiisoft/yii2/blob/22.0/framework/base/Model.php#L73) |

8 subclasses:

- [`DynamicModel`](/docs/api/yii/base/dynamicmodel/index.md)
- [`yii\data\DataFilter`](/docs/api/yii/data/datafilter/index.md)
- [`yii\db\BaseActiveRecord`](/docs/api/yii/db/baseactiverecord/index.md)
- [`yii\debug\models\UserSwitch`](/docs/extensions/debug/reference/models/userswitch/index.md)
- [`yii\debug\models\router\ActionRoutes`](/docs/extensions/debug/reference/models/router/actionroutes/index.md)
- [`yii\debug\models\router\RouterRules`](/docs/extensions/debug/reference/models/router/routerrules/index.md)
- [`yii\debug\models\search\Base`](/docs/extensions/debug/reference/models/search/base/index.md)
- [`yii\debug\models\search\UserSearch`](/docs/extensions/debug/reference/models/search/usersearch/index.md)

Model is the base class for data models.

Model implements the following commonly used features:

- attribute declaration: by default, every public class member is considered as
  a model attribute
- attribute labels: each attribute may be associated with a label for display purpose
- massive attribute assignment
- scenario-based validation

Model also raises the following events when performing data validation:

- [`EVENT_BEFORE_VALIDATE`](/docs/api/yii/base/model/index.md#event-EVENT_BEFORE_VALIDATE): an event raised at the beginning of [`validate()`](/docs/api/yii/base/model/index.md#method-validate)
- [`EVENT_AFTER_VALIDATE`](/docs/api/yii/base/model/index.md#event-EVENT_AFTER_VALIDATE): an event raised at the end of [`validate()`](/docs/api/yii/base/model/index.md#method-validate)

You may directly use Model to store model data, or extend it with customization.

For more details and usage information on Model, see the [guide article on models](/docs/guide/structure-models/index.md).

## Properties

| Property | Type | Description | Defined by |
| --- | --- | --- | --- |
| <span id="property-activeValidators"></span>`$activeValidators` read-only | [`yii\validators\Validator`](/docs/api/yii/validators/validator/index.md)`[]` | The validators applicable to the current [`$scenario`](/docs/api/yii/base/model/index.md#property-scenario). | `Model` |
| <span id="property-attributes"></span>`$attributes` | `array<string, mixed>` | Attribute values (name => value). | `Model` |
| <span id="property-behaviors"></span>[`$behaviors`](/docs/api/yii/base/component/index.md#property-behaviors) read-only | `array<`[`Behavior`](/docs/api/yii/base/behavior/index.md)`<static>>` | List of behaviors attached to this component. | [`Component`](/docs/api/yii/base/component/index.md) |
| [`$errors`](#property-errors) read-only | `array<string, string[]>` | Errors for all attributes. | `Model` |
| [`$firstErrors`](#property-firstErrors) read-only | `array<string, string>` | The first errors. | `Model` |
| <span id="property-iterator"></span>`$iterator` read-only | [`ArrayIterator`](https://www.php.net/manual/en/class.arrayiterator.php)`<string, mixed>` | An iterator for traversing the items in the list. | `Model` |
| [`$scenario`](#property-scenario) | `string` | The scenario that this model is in. | `Model` |
| <span id="property-validators"></span>`$validators` read-only | [`ArrayObject`](https://www.php.net/manual/en/class.arrayobject.php)`<int,` [`yii\validators\Validator`](/docs/api/yii/validators/validator/index.md)`>\|`[`yii\validators\Validator`](/docs/api/yii/validators/validator/index.md)`[]` | All the validators declared in the model. | `Model` |

## Methods

| Method | Description | Defined by |
| --- | --- | --- |
| <span id="method-__construct"></span>[`__construct()`](/docs/api/yii/base/baseobject/index.md#method-__construct) | Constructor. | [`BaseObject`](/docs/api/yii/base/baseobject/index.md) |
| <span id="method-__call"></span>[`__call()`](/docs/api/yii/base/component/index.md#method-__call) | Calls the named method which is not a class method. | [`Component`](/docs/api/yii/base/component/index.md) |
| [`__clone()`](#method-__clone) | This method is called after the object is created by cloning an existing one. | `Model` |
| <span id="method-__get"></span>[`__get()`](/docs/api/yii/base/component/index.md#method-__get) | Returns the value of a component property. | [`Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-__isset"></span>[`__isset()`](/docs/api/yii/base/component/index.md#method-__isset) | Checks if a property is set, i.e. defined and not null. | [`Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-__set"></span>[`__set()`](/docs/api/yii/base/component/index.md#method-__set) | Sets the value of a component property. | [`Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-__unset"></span>[`__unset()`](/docs/api/yii/base/component/index.md#method-__unset) | Sets a component property to be null. | [`Component`](/docs/api/yii/base/component/index.md) |
| [`activeAttributes()`](#method-activeAttributes) | Returns the attribute names that are subject to validation in the current scenario. | `Model` |
| [`addError()`](#method-addError) | Adds a new error to the specified attribute. | `Model` |
| [`addErrors()`](#method-addErrors) | Adds a list of errors. | `Model` |
| [`afterValidate()`](#method-afterValidate) | This method is invoked after validation ends. | `Model` |
| <span id="method-attachBehavior"></span>[`attachBehavior()`](/docs/api/yii/base/component/index.md#method-attachBehavior) | Attaches a behavior to this component. | [`Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-attachBehaviors"></span>[`attachBehaviors()`](/docs/api/yii/base/component/index.md#method-attachBehaviors) | Attaches a list of behaviors to the component. | [`Component`](/docs/api/yii/base/component/index.md) |
| [`attributeHints()`](#method-attributeHints) | Returns the attribute hints. | `Model` |
| [`attributeLabels()`](#method-attributeLabels) | Returns the attribute labels. | `Model` |
| [`attributes()`](#method-attributes) | Returns the list of attribute names. | `Model` |
| [`beforeValidate()`](#method-beforeValidate) | This method is invoked before validation starts. | `Model` |
| <span id="method-behaviors"></span>[`behaviors()`](/docs/api/yii/base/component/index.md#method-behaviors) | Returns a list of behaviors that this component should behave as. | [`Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-canGetProperty"></span>[`canGetProperty()`](/docs/api/yii/base/component/index.md#method-canGetProperty) | Returns a value indicating whether a property can be read. | [`Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-canSetProperty"></span>[`canSetProperty()`](/docs/api/yii/base/component/index.md#method-canSetProperty) | Returns a value indicating whether a property can be set. | [`Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-className"></span>[`className()`](/docs/api/yii/base/baseobject/index.md#method-className) static | Returns the fully qualified name of this class. | [`BaseObject`](/docs/api/yii/base/baseobject/index.md) |
| [`clearErrors()`](#method-clearErrors) | Removes errors for all attributes or a single attribute. | `Model` |
| [`createValidators()`](#method-createValidators) | Creates validator objects based on the validation rules specified in [`rules()`](/docs/api/yii/base/model/index.md#method-rules). | `Model` |
| <span id="method-detachBehavior"></span>[`detachBehavior()`](/docs/api/yii/base/component/index.md#method-detachBehavior) | Detaches a behavior from the component. | [`Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-detachBehaviors"></span>[`detachBehaviors()`](/docs/api/yii/base/component/index.md#method-detachBehaviors) | Detaches all behaviors from the component. | [`Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-ensureBehaviors"></span>[`ensureBehaviors()`](/docs/api/yii/base/component/index.md#method-ensureBehaviors) | Makes sure that the behaviors declared in [`behaviors()`](/docs/api/yii/base/component/index.md#method-behaviors) are attached to this component. | [`Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-extraFields"></span>[`extraFields()`](/docs/api/yii/base/arrayabletrait/index.md#method-extraFields) | Returns the list of fields that can be expanded further and returned by [`toArray()`](/docs/api/yii/base/arrayabletrait/index.md#method-toArray). | [`ArrayableTrait`](/docs/api/yii/base/arrayabletrait/index.md) |
| [`fields()`](#method-fields) | Returns the list of fields that should be returned by default by [`toArray()`](/docs/api/yii/base/arrayabletrait/index.md#method-toArray) when no specific fields are specified. | `Model` |
| [`formName()`](#method-formName) | Returns the form name that this model class should use. | `Model` |
| [`generateAttributeLabel()`](#method-generateAttributeLabel) | Generates a user friendly attribute label based on the give attribute name. | `Model` |
| [`getActiveValidators()`](#method-getActiveValidators) | Returns the validators applicable to the current [`$scenario`](/docs/api/yii/base/model/index.md#property-scenario). | `Model` |
| [`getAttributeHint()`](#method-getAttributeHint) | Returns the text hint for the specified attribute. | `Model` |
| [`getAttributeLabel()`](#method-getAttributeLabel) | Returns the text label for the specified attribute. | `Model` |
| [`getAttributes()`](#method-getAttributes) | Returns attribute values. | `Model` |
| <span id="method-getBehavior"></span>[`getBehavior()`](/docs/api/yii/base/component/index.md#method-getBehavior) | Returns the named behavior object. | [`Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-getBehaviors"></span>[`getBehaviors()`](/docs/api/yii/base/component/index.md#method-getBehaviors) | Returns all behaviors attached to this component. | [`Component`](/docs/api/yii/base/component/index.md) |
| [`getErrors()`](#method-getErrors) | Returns the errors for all attributes or a single attribute. | `Model` |
| [`getErrorSummary()`](#method-getErrorSummary) | Returns the errors for all attributes as a one-dimensional array. | `Model` |
| [`getFirstError()`](#method-getFirstError) | Returns the first error of the specified attribute. | `Model` |
| [`getFirstErrors()`](#method-getFirstErrors) | Returns the first error of every attribute in the model. | `Model` |
| [`getIterator()`](#method-getIterator) | Returns an iterator for traversing the attributes in the model. | `Model` |
| [`getScenario()`](#method-getScenario) | Returns the scenario that this model is used in. | `Model` |
| [`getValidators()`](#method-getValidators) | Returns all the validators declared in [`rules()`](/docs/api/yii/base/model/index.md#method-rules). | `Model` |
| [`hasErrors()`](#method-hasErrors) | Returns a value indicating whether there is any validation error. | `Model` |
| <span id="method-hasEventHandlers"></span>[`hasEventHandlers()`](/docs/api/yii/base/component/index.md#method-hasEventHandlers) | Returns a value indicating whether there is any handler attached to the named event. | [`Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-hasMethod"></span>[`hasMethod()`](/docs/api/yii/base/component/index.md#method-hasMethod) | Returns a value indicating whether a method is defined. | [`Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-hasProperty"></span>[`hasProperty()`](/docs/api/yii/base/component/index.md#method-hasProperty) | Returns a value indicating whether a property is defined for this component. | [`Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-init"></span>[`init()`](/docs/api/yii/base/baseobject/index.md#method-init) | Initializes the object. | [`BaseObject`](/docs/api/yii/base/baseobject/index.md) |
| <span id="method-instance"></span>[`instance()`](/docs/api/yii/base/staticinstancetrait/index.md#method-instance) static | Returns static class instance, which can be used to obtain meta information. | [`StaticInstanceTrait`](/docs/api/yii/base/staticinstancetrait/index.md) |
| [`isAttributeActive()`](#method-isAttributeActive) | Returns a value indicating whether the attribute is active in the current scenario. | `Model` |
| [`isAttributeRequired()`](#method-isAttributeRequired) | Returns a value indicating whether the attribute is required. | `Model` |
| [`isAttributeSafe()`](#method-isAttributeSafe) | Returns a value indicating whether the attribute is safe for massive assignments. | `Model` |
| [`load()`](#method-load) | Populates the model with input data. | `Model` |
| [`loadMultiple()`](#method-loadMultiple) static | Populates a set of models with the data from end user. | `Model` |
| <span id="method-off"></span>[`off()`](/docs/api/yii/base/component/index.md#method-off) | Detaches an existing event handler from this component. | [`Component`](/docs/api/yii/base/component/index.md) |
| [`offsetExists()`](#method-offsetExists) | Returns whether there is an element at the specified offset. | `Model` |
| [`offsetGet()`](#method-offsetGet) | Returns the element at the specified offset. | `Model` |
| [`offsetSet()`](#method-offsetSet) | Sets the element at the specified offset. | `Model` |
| [`offsetUnset()`](#method-offsetUnset) | Sets the element value at the specified offset to null. | `Model` |
| <span id="method-on"></span>[`on()`](/docs/api/yii/base/component/index.md#method-on) | Attaches an event handler to an event. | [`Component`](/docs/api/yii/base/component/index.md) |
| [`onUnsafeAttribute()`](#method-onUnsafeAttribute) | This method is invoked when an unsafe attribute is being massively assigned. | `Model` |
| [`rules()`](#method-rules) | Returns the validation rules for attributes. | `Model` |
| [`safeAttributes()`](#method-safeAttributes) | Returns the attribute names that are safe to be massively assigned in the current scenario. | `Model` |
| [`scenarios()`](#method-scenarios) | Returns a list of scenarios and the corresponding active attributes. | `Model` |
| [`setAttributes()`](#method-setAttributes) | Sets the attribute values in a massive way. | `Model` |
| [`setScenario()`](#method-setScenario) | Sets the scenario for the model. | `Model` |
| <span id="method-toArray"></span>[`toArray()`](/docs/api/yii/base/arrayabletrait/index.md#method-toArray) | Converts the model into an array. | [`ArrayableTrait`](/docs/api/yii/base/arrayabletrait/index.md) |
| <span id="method-trigger"></span>[`trigger()`](/docs/api/yii/base/component/index.md#method-trigger) | Triggers an event. | [`Component`](/docs/api/yii/base/component/index.md) |
| [`validate()`](#method-validate) | Performs the data validation. | `Model` |
| [`validateMultiple()`](#method-validateMultiple) static | Validates multiple models. | `Model` |
| <span id="method-extractFieldsFor"></span>[`extractFieldsFor()`](/docs/api/yii/base/arrayabletrait/index.md#method-extractFieldsFor) protected | Extract nested fields from a fields collection for a given root field Nested fields are separated with dots (.). e.g: "item.id" The previous example would extract "id". | [`ArrayableTrait`](/docs/api/yii/base/arrayabletrait/index.md) |
| <span id="method-extractRootFields"></span>[`extractRootFields()`](/docs/api/yii/base/arrayabletrait/index.md#method-extractRootFields) protected | Extracts the root field names from nested fields. | [`ArrayableTrait`](/docs/api/yii/base/arrayabletrait/index.md) |
| <span id="method-resolveFields"></span>[`resolveFields()`](/docs/api/yii/base/arrayabletrait/index.md#method-resolveFields) protected | Determines which fields can be returned by [`toArray()`](/docs/api/yii/base/arrayabletrait/index.md#method-toArray). | [`ArrayableTrait`](/docs/api/yii/base/arrayabletrait/index.md) |

## Events

| Event | Type | Description | Defined by |
| --- | --- | --- | --- |
| <span id="event-EVENT_BEFORE_VALIDATE"></span>`EVENT_BEFORE_VALIDATE` | [`ModelEvent`](/docs/api/yii/base/modelevent/index.md) | An event raised at the beginning of [`validate()`](/docs/api/yii/base/model/index.md#method-validate). Event name: `'beforeValidate'`. | `Model` |
| <span id="event-EVENT_AFTER_VALIDATE"></span>`EVENT_AFTER_VALIDATE` | [`Event`](/docs/api/yii/base/event/index.md) | An event raised at the end of [`validate()`](/docs/api/yii/base/model/index.md#method-validate) Event name: `'afterValidate'`. | `Model` |

## Constants

| Constant | Value | Description | Defined by |
| --- | --- | --- | --- |
| <span id="const-SCENARIO_DEFAULT"></span>`SCENARIO_DEFAULT` | `'default'` | The name of the default scenario. | `Model` |

## Property details

### $errors <span id="property-errors"></span>

```php
public array<string, string[]> $errors
```

Errors for all attributes.

This is a two-dimensional
array of errors for all attributes, similar to the following:

```
[
    'username' => [
        'Username is required.',
        'Username must contain only word characters.',
    ],
    'email' => [
        'Email address is invalid.',
    ]
]
```

Empty array if no errors.

**Access**

Read-only (virtual property).

### $firstErrors <span id="property-firstErrors"></span>

```php
public array<string, string> $firstErrors
```

The first errors.

The array keys are the attribute names,
and the array values are the corresponding error messages. An empty array will be returned if there is no
error.

**Access**

Read-only (virtual property).

### $scenario <span id="property-scenario"></span>

```php
public string $scenario
```

The scenario that this model is in.

Defaults to [`SCENARIO_DEFAULT`](/docs/api/yii/base/model/index.md#const-SCENARIO_DEFAULT).

## Method details

### __clone() <span id="method-__clone"></span>

```php
public function __clone(): mixed
```

This method is called after the object is created by cloning an existing one.

It removes all behaviors because they are attached to the old object.

**Returns**

`mixed`

### activeAttributes() <span id="method-activeAttributes"></span>

```php
public function activeAttributes(): string[]
```

Returns the attribute names that are subject to validation in the current scenario.

**Returns**

`string[]`: Safe attribute names

### addError() <span id="method-addError"></span>

```php
public function addError(string $attribute, string $error = ''): mixed
```

Adds a new error to the specified attribute.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$attribute` | `string` | Attribute name |
| `$error` | `string` | New error message |

**Returns**

`mixed`

### addErrors() <span id="method-addErrors"></span>

```php
public function addErrors(array $items): mixed
```

Adds a list of errors.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$items` | `array` | A list of errors. The array keys must be attribute names. The array values should be error messages. If an attribute has multiple errors, these errors must be given in terms of an array. You may use the result of [`getErrors()`](/docs/api/yii/base/model/index.md#method-getErrors) as the value for this parameter. |

**Returns**

`mixed`

**Since**

2.0.2

### afterValidate() <span id="method-afterValidate"></span>

```php
public function afterValidate(): mixed
```

This method is invoked after validation ends.

The default implementation raises an `afterValidate` event.
You may override this method to do postprocessing after validation.
Make sure the parent implementation is invoked so that the event can be raised.

**Returns**

`mixed`

### attributeHints() <span id="method-attributeHints"></span>

```php
public function attributeHints(): array<string, string>
```

Returns the attribute hints.

Attribute hints are mainly used for display purpose. For example, given an attribute
`isPublic`, we can declare a hint `Whether the post should be visible for not logged in users`,
which provides user-friendly description of the attribute meaning and can be displayed to end users.

Unlike label hint will not be generated, if its explicit declaration is omitted.

Note, in order to inherit hints defined in the parent class, a child class needs to
merge the parent hints with child hints using functions such as `array_merge()`.

**Returns**

`array<string, string>`: Attribute hints (name => hint)

**Since**

2.0.4

### attributeLabels() <span id="method-attributeLabels"></span>

```php
public function attributeLabels(): array<string, string>
```

Returns the attribute labels.

Attribute labels are mainly used for display purpose. For example, given an attribute
`firstName`, we can declare a label `First Name` which is more user-friendly and can
be displayed to end users.

By default an attribute label is generated using [`generateAttributeLabel()`](/docs/api/yii/base/model/index.md#method-generateAttributeLabel).
This method allows you to explicitly specify attribute labels.

Note, in order to inherit labels defined in the parent class, a child class needs to
merge the parent labels with child labels using functions such as `array_merge()`.

**Returns**

`array<string, string>`: Attribute labels (name => label)

**See also**

- [`generateAttributeLabel()`](/docs/api/yii/base/model/index.md#method-generateAttributeLabel)

### attributes() <span id="method-attributes"></span>

```php
public function attributes(): string[]
```

Returns the list of attribute names.

By default, this method returns all public non-static properties of the class.
You may override this method to change the default behavior.

**Returns**

`string[]`: List of attribute names.

### beforeValidate() <span id="method-beforeValidate"></span>

```php
public function beforeValidate(): bool
```

This method is invoked before validation starts.

The default implementation raises a `beforeValidate` event.
You may override this method to do preliminary checks before validation.
Make sure the parent implementation is invoked so that the event can be raised.

**Returns**

`bool`: Whether the validation should be executed. Defaults to true. If false is returned, the validation will stop and the model is considered invalid.

### clearErrors() <span id="method-clearErrors"></span>

```php
public function clearErrors(string|null $attribute = null): mixed
```

Removes errors for all attributes or a single attribute.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$attribute` | `string\|null` | Attribute name. Use null to remove errors for all attributes. |

**Returns**

`mixed`

### createValidators() <span id="method-createValidators"></span>

```php
public function createValidators(): ArrayObject<int, yii\validators\Validator>
```

Creates validator objects based on the validation rules specified in [`rules()`](/docs/api/yii/base/model/index.md#method-rules).

Unlike [`getValidators()`](/docs/api/yii/base/model/index.md#method-getValidators), each time this method is called, a new list of validators will be returned.

**Returns**

[`ArrayObject`](https://www.php.net/manual/en/class.arrayobject.php)`<int,` [`yii\validators\Validator`](/docs/api/yii/validators/validator/index.md)`>`: Validators

**Throws**

- [`InvalidConfigException`](/docs/api/yii/base/invalidconfigexception/index.md): if any validation rule configuration is invalid

### fields() <span id="method-fields"></span>

```php
public function fields(): array
```

Returns the list of fields that should be returned by default by [`toArray()`](/docs/api/yii/base/arrayabletrait/index.md#method-toArray) when no specific fields are specified.

A field is a named element in the returned array by [`toArray()`](/docs/api/yii/base/arrayabletrait/index.md#method-toArray).

This method should return an array of field names or field definitions.
If the former, the field name will be treated as an object property name whose value will be used
as the field value. If the latter, the array key should be the field name while the array value should be
the corresponding field definition which can be either an object property name or a PHP callable
returning the corresponding field value. The signature of the callable should be:

```
function ($model, $field) {
    // return field value
}
```

For example, the following code declares four fields:

- `email`: the field name is the same as the property name `email`;
- `firstName` and `lastName`: the field names are `firstName` and `lastName`, and their
  values are obtained from the `first_name` and `last_name` properties;
- `fullName`: the field name is `fullName`. Its value is obtained by concatenating `first_name`
  and `last_name`.

```
return [
    'email',
    'firstName' => 'first_name',
    'lastName' => 'last_name',
    'fullName' => function ($model) {
        return $model->first_name . ' ' . $model->last_name;
    },
];
```

In this method, you may also want to return different lists of fields based on some context
information. For example, depending on [`$scenario`](/docs/api/yii/base/model/index.md#property-scenario) or the privilege of the current application user,
you may return different sets of visible fields or filter out some fields.

The default implementation of this method returns [`attributes()`](/docs/api/yii/base/model/index.md#method-attributes) indexed by the same attribute names.

**Returns**

`array`: The list of field names or field definitions.

**See also**

- [`toArray()`](/docs/api/yii/base/arrayabletrait/index.md#method-toArray)

### formName() <span id="method-formName"></span>

```php
public function formName(): string
```

Returns the form name that this model class should use.

The form name is mainly used by [`ActiveForm`](/docs/api/yii/widgets/activeform/index.md) to determine how to name
the input fields for the attributes in a model. If the form name is "A" and an attribute
name is "b", then the corresponding input name would be "A[b]". If the form name is
an empty string, then the input name would be "b".

The purpose of the above naming schema is that for forms which contain multiple different models,
the attributes of each model are grouped in sub-arrays of the POST-data and it is easier to
differentiate between them.

By default, this method returns the model class name (without the namespace part)
as the form name. You may override it when the model is used in different forms.

**Returns**

`string`: The form name of this model class.

**Throws**

- [`InvalidConfigException`](/docs/api/yii/base/invalidconfigexception/index.md): when form is defined with anonymous class and `formName()` method is not overridden.

**See also**

- [`load()`](/docs/api/yii/base/model/index.md#method-load)

### generateAttributeLabel() <span id="method-generateAttributeLabel"></span>

```php
public function generateAttributeLabel(string $name): string
```

Generates a user friendly attribute label based on the give attribute name.

This is done by replacing underscores, dashes and dots with blanks and
changing the first letter of each word to upper case.
For example, 'department_name' or 'DepartmentName' will generate 'Department Name'.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$name` | `string` | The column name |

**Returns**

`string`: The attribute label

### getActiveValidators() <span id="method-getActiveValidators"></span>

```php
public function getActiveValidators(string|null $attribute = null): yii\validators\Validator[]
```

Returns the validators applicable to the current [`$scenario`](/docs/api/yii/base/model/index.md#property-scenario).

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$attribute` | `string\|null` | The name of the attribute whose applicable validators should be returned. If this is null, the validators for ALL attributes in the model will be returned. |

**Returns**

[`yii\validators\Validator`](/docs/api/yii/validators/validator/index.md)`[]`: The validators applicable to the current [`$scenario`](/docs/api/yii/base/model/index.md#property-scenario).

### getAttributeHint() <span id="method-getAttributeHint"></span>

```php
public function getAttributeHint(string $attribute): string
```

Returns the text hint for the specified attribute.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$attribute` | `string` | The attribute name |

**Returns**

`string`: The attribute hint

**Since**

2.0.4

**See also**

- [`attributeHints()`](/docs/api/yii/base/model/index.md#method-attributeHints)

### getAttributeLabel() <span id="method-getAttributeLabel"></span>

```php
public function getAttributeLabel(string $attribute): string
```

Returns the text label for the specified attribute.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$attribute` | `string` | The attribute name |

**Returns**

`string`: The attribute label

**See also**

- [`generateAttributeLabel()`](/docs/api/yii/base/model/index.md#method-generateAttributeLabel)
- [`attributeLabels()`](/docs/api/yii/base/model/index.md#method-attributeLabels)

### getAttributes() <span id="method-getAttributes"></span>

```php
public function getAttributes(array|null $names = null, array $except = []): array<string, mixed>
```

Returns attribute values.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$names` | `array\|null` | List of attributes whose value needs to be returned. Defaults to null, meaning all attributes listed in [`attributes()`](/docs/api/yii/base/model/index.md#method-attributes) will be returned. If it is an array, only the attributes in the array will be returned. |
| `$except` | `array` | List of attributes whose value should NOT be returned. |

**Returns**

`array<string, mixed>`: Attribute values (name => value).

### getErrors() <span id="method-getErrors"></span>

```php
public function getErrors(string|null $attribute = null): ($attribute is null ? array<string, string[]> : string[])
```

Returns the errors for all attributes or a single attribute.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$attribute` | `string\|null` | Attribute name. Use null to retrieve errors for all attributes. |

**Returns**

`($attribute is null ? array<string, string[]> : string[])`: Errors for all attributes or the specified attribute. Empty array is returned if no error. Note that when returning errors for all attributes, the result is a two-dimensional array, like the following: [ 'username' => [ 'Username is required.', 'Username must contain only word characters.', ], 'email' => [ 'Email address is invalid.', ] ]

**See also**

- [`getFirstErrors()`](/docs/api/yii/base/model/index.md#method-getFirstErrors)
- [`getFirstError()`](/docs/api/yii/base/model/index.md#method-getFirstError)

### getErrorSummary() <span id="method-getErrorSummary"></span>

```php
public function getErrorSummary(bool $showAllErrors): string[]
```

Returns the errors for all attributes as a one-dimensional array.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$showAllErrors` | `bool` | Boolean, if set to true every error message for each attribute will be shown otherwise only the first error message for each attribute will be shown. |

**Returns**

`string[]`: Errors for all attributes as a one-dimensional array. Empty array is returned if no error.

**Since**

2.0.14

**See also**

- [`getErrors()`](/docs/api/yii/base/model/index.md#method-getErrors)
- [`getFirstErrors()`](/docs/api/yii/base/model/index.md#method-getFirstErrors)

### getFirstError() <span id="method-getFirstError"></span>

```php
public function getFirstError(string $attribute): string|null
```

Returns the first error of the specified attribute.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$attribute` | `string` | Attribute name. |

**Returns**

`string|null`: The error message. Null is returned if no error.

**See also**

- [`getErrors()`](/docs/api/yii/base/model/index.md#method-getErrors)
- [`getFirstErrors()`](/docs/api/yii/base/model/index.md#method-getFirstErrors)

### getFirstErrors() <span id="method-getFirstErrors"></span>

```php
public function getFirstErrors(): array<string, string>
```

Returns the first error of every attribute in the model.

**Returns**

`array<string, string>`: The first errors. The array keys are the attribute names, and the array values are the corresponding error messages. An empty array will be returned if there is no error.

**See also**

- [`getErrors()`](/docs/api/yii/base/model/index.md#method-getErrors)
- [`getFirstError()`](/docs/api/yii/base/model/index.md#method-getFirstError)

### getIterator() <span id="method-getIterator"></span>

```php
public function getIterator(): ArrayIterator<string, mixed>
```

Returns an iterator for traversing the attributes in the model.

This method is required by the interface [`IteratorAggregate`](https://www.php.net/manual/en/class.iteratoraggregate.php).

**Returns**

[`ArrayIterator`](https://www.php.net/manual/en/class.arrayiterator.php)`<string, mixed>`: An iterator for traversing the items in the list.

### getScenario() <span id="method-getScenario"></span>

```php
public function getScenario(): string
```

Returns the scenario that this model is used in.

Scenario affects how validation is performed and which attributes can
be massively assigned.

**Returns**

`string`: The scenario that this model is in. Defaults to [`SCENARIO_DEFAULT`](/docs/api/yii/base/model/index.md#const-SCENARIO_DEFAULT).

### getValidators() <span id="method-getValidators"></span>

```php
public function getValidators(): ArrayObject<int, yii\validators\Validator>|yii\validators\Validator[]
```

Returns all the validators declared in [`rules()`](/docs/api/yii/base/model/index.md#method-rules).

This method differs from [`getActiveValidators()`](/docs/api/yii/base/model/index.md#method-getActiveValidators) in that the latter
only returns the validators applicable to the current [`$scenario`](/docs/api/yii/base/model/index.md#property-scenario).

Because this method returns an ArrayObject object, you may
manipulate it by inserting or removing validators (useful in model behaviors).
For example,

```
$model->validators[] = $newValidator;
```

**Returns**

[`ArrayObject`](https://www.php.net/manual/en/class.arrayobject.php)`<int,` [`yii\validators\Validator`](/docs/api/yii/validators/validator/index.md)`>|`[`yii\validators\Validator`](/docs/api/yii/validators/validator/index.md)`[]`: All the validators declared in the model.

### hasErrors() <span id="method-hasErrors"></span>

```php
public function hasErrors(string|null $attribute = null): bool
```

Returns a value indicating whether there is any validation error.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$attribute` | `string\|null` | Attribute name. Use null to check all attributes. |

**Returns**

`bool`: Whether there is any error.

### isAttributeActive() <span id="method-isAttributeActive"></span>

```php
public function isAttributeActive(string $attribute): bool
```

Returns a value indicating whether the attribute is active in the current scenario.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$attribute` | `string` | Attribute name |

**Returns**

`bool`: Whether the attribute is active in the current scenario

**See also**

- [`activeAttributes()`](/docs/api/yii/base/model/index.md#method-activeAttributes)

### isAttributeRequired() <span id="method-isAttributeRequired"></span>

```php
public function isAttributeRequired(string $attribute): bool
```

Returns a value indicating whether the attribute is required.

This is determined by checking if the attribute is associated with a
[required](/docs/api/yii/validators/requiredvalidator/index.md) validation rule in the
current [`$scenario`](/docs/api/yii/base/model/index.md#property-scenario).

Note that when the validator has a conditional validation applied using
[$when](/docs/api/yii/validators/validator/index.md#property-when) this method will return
`false` regardless of the `when` condition because it may be called be
before the model is loaded with data.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$attribute` | `string` | Attribute name |

**Returns**

`bool`: Whether the attribute is required

### isAttributeSafe() <span id="method-isAttributeSafe"></span>

```php
public function isAttributeSafe(string $attribute): bool
```

Returns a value indicating whether the attribute is safe for massive assignments.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$attribute` | `string` | Attribute name |

**Returns**

`bool`: Whether the attribute is safe for massive assignments

**See also**

- [`safeAttributes()`](/docs/api/yii/base/model/index.md#method-safeAttributes)

### load() <span id="method-load"></span>

```php
public function load(array $data, string|null $formName = null): bool
```

Populates the model with input data.

This method provides a convenient shortcut for:

```
if (isset($_POST['FormName'])) {
    $model->attributes = $_POST['FormName'];
    if ($model->save()) {
        // handle success
    }
}
```

which, with `load()` can be written as:

```
if ($model->load($_POST) && $model->save()) {
    // handle success
}
```

`load()` gets the `'FormName'` from the model's [`formName()`](/docs/api/yii/base/model/index.md#method-formName) method (which you may override), unless the
`$formName` parameter is given. If the form name is empty, `load()` populates the model with the whole of `$data`,
instead of `$data['FormName']`.

Note, that the data being populated is subject to the safety check by [`setAttributes()`](/docs/api/yii/base/model/index.md#method-setAttributes).

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$data` | `array` | The data array to load, typically `$_POST` or `$_GET`. |
| `$formName` | `string\|null` | The form name to use to load the data into the model, empty string when form not use. If not set, [`formName()`](/docs/api/yii/base/model/index.md#method-formName) is used. |

**Returns**

`bool`: Whether `load()` found the expected form in `$data`.

### loadMultiple() <span id="method-loadMultiple"></span>

```php
public static function loadMultiple(array $models, array $data, string|null $formName = null): bool
```

Populates a set of models with the data from end user.

This method is mainly used to collect tabular data input.
The data to be loaded for each model is `$data[formName][index]`, where `formName`
refers to the value of [`formName()`](/docs/api/yii/base/model/index.md#method-formName), and `index` the index of the model in the `$models` array.
If [`formName()`](/docs/api/yii/base/model/index.md#method-formName) is empty, `$data[index]` will be used to populate each model.
The data being populated to each model is subject to the safety check by [`setAttributes()`](/docs/api/yii/base/model/index.md#method-setAttributes).

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$models` | `array` | The models to be populated. Note that all models should have the same class. |
| `$data` | `array` | The data array. This is usually `$_POST` or `$_GET`, but can also be any valid array supplied by end user. |
| `$formName` | `string\|null` | The form name to be used for loading the data into the models. If not set, it will use the [`formName()`](/docs/api/yii/base/model/index.md#method-formName) value of the first model in `$models`. This parameter is available since version 2.0.1. |

**Returns**

`bool`: Whether at least one of the models is successfully populated.

### offsetExists() <span id="method-offsetExists"></span>

```php
public function offsetExists(string $offset): bool
```

Returns whether there is an element at the specified offset.

This method is required by the SPL interface [`ArrayAccess`](https://www.php.net/manual/en/class.arrayaccess.php).
It is implicitly called when you use something like `isset($model[$offset])`.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$offset` | `string` | The offset to check on. |

**Returns**

`bool`: Whether or not an offset exists.

### offsetGet() <span id="method-offsetGet"></span>

```php
public function offsetGet(string $offset): mixed
```

Returns the element at the specified offset.

This method is required by the SPL interface [`ArrayAccess`](https://www.php.net/manual/en/class.arrayaccess.php).
It is implicitly called when you use something like `$value = $model[$offset];`.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$offset` | `string` | The offset to retrieve element. |

**Returns**

`mixed`: The element at the offset, null if no element is found at the offset

### offsetSet() <span id="method-offsetSet"></span>

```php
public function offsetSet(string $offset, mixed $value): mixed
```

Sets the element at the specified offset.

This method is required by the SPL interface [`ArrayAccess`](https://www.php.net/manual/en/class.arrayaccess.php).
It is implicitly called when you use something like `$model[$offset] = $value;`.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$offset` | `string` | The offset to set element |
| `$value` | `mixed` | The element value |

**Returns**

`mixed`

### offsetUnset() <span id="method-offsetUnset"></span>

```php
public function offsetUnset(string $offset): mixed
```

Sets the element value at the specified offset to null.

This method is required by the SPL interface [`ArrayAccess`](https://www.php.net/manual/en/class.arrayaccess.php).
It is implicitly called when you use something like `unset($model[$offset])`.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$offset` | `string` | The offset to unset element |

**Returns**

`mixed`

### onUnsafeAttribute() <span id="method-onUnsafeAttribute"></span>

```php
public function onUnsafeAttribute(string $name, mixed $value): mixed
```

This method is invoked when an unsafe attribute is being massively assigned.

The default implementation will log a warning message if YII_DEBUG is on.
It does nothing otherwise.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$name` | `string` | The unsafe attribute name |
| `$value` | `mixed` | The attribute value |

**Returns**

`mixed`

### rules() <span id="method-rules"></span>

```php
public function rules(): array<int, array<array-key, mixed>|yii\validators\Validator>
```

Returns the validation rules for attributes.

Validation rules are used by [`validate()`](/docs/api/yii/base/model/index.md#method-validate) to check if attribute values are valid.
Child classes may override this method to declare different validation rules.

Each rule is an array with the following structure:

```
[
    ['attribute1', 'attribute2'],
    'validator type',
    'on' => ['scenario1', 'scenario2'],
    //...other parameters...
]
```

where

 - attribute list: required, specifies the attributes array to be validated, for single attribute you can pass a string;
 - validator type: required, specifies the validator to be used. It can be a built-in validator name,
   a method name of the model class, an anonymous function, or a validator class name.
 - on: optional, specifies the [scenarios](/docs/api/yii/base/model/index.md#property-scenario) array in which the validation
   rule can be applied. If this option is not set, the rule will apply to all scenarios.
 - additional name-value pairs can be specified to initialize the corresponding validator properties.
   Please refer to individual validator class API for possible properties.

A validator can be either an object of a class extending [`Validator`](/docs/api/yii/validators/validator/index.md), or a model class method
(called *inline validator*) that has the following signature:

```
// $params refers to validation parameters given in the rule
function validatorName($attribute, $params)
```

In the above `$attribute` refers to the attribute currently being validated while `$params` contains an array of
validator configuration options such as `max` in case of `string` validator. The value of the attribute currently being validated
can be accessed as `$this->$attribute`. Note the `$` before `attribute`; this is taking the value of the variable
`$attribute` and using it as the name of the property to access.

Yii also provides a set of [built-in validators](/docs/api/yii/validators/validator/index.md#property-builtInValidators).
Each one has an alias name which can be used when specifying a validation rule.

Below are some examples:

```
[
    // built-in "required" validator
    [['username', 'password'], 'required'],
    // built-in "string" validator customized with "min" and "max" properties
    ['username', 'string', 'min' => 3, 'max' => 12],
    // built-in "compare" validator that is used in "register" scenario only
    ['password', 'compare', 'compareAttribute' => 'password2', 'on' => 'register'],
    // an inline validator defined via the "authenticate()" method in the model class
    ['password', 'authenticate', 'on' => 'login'],
    // a validator of class "DateRangeValidator"
    ['dateRange', 'DateRangeValidator'],
];
```

Note, in order to inherit rules defined in the parent class, a child class needs to
merge the parent rules with child rules using functions such as `array_merge()`.

**Returns**

`array<int, array<array-key, mixed>|`[`yii\validators\Validator`](/docs/api/yii/validators/validator/index.md)`>`: Validation rules

**See also**

- [`scenarios()`](/docs/api/yii/base/model/index.md#method-scenarios)

### safeAttributes() <span id="method-safeAttributes"></span>

```php
public function safeAttributes(): string[]
```

Returns the attribute names that are safe to be massively assigned in the current scenario.

**Returns**

`string[]`: Safe attribute names

### scenarios() <span id="method-scenarios"></span>

```php
public function scenarios(): array<string, string[]>
```

Returns a list of scenarios and the corresponding active attributes.

An active attribute is one that is subject to validation in the current scenario.
The returned array should be in the following format:

```
[
    'scenario1' => ['attribute11', 'attribute12', ...],
    'scenario2' => ['attribute21', 'attribute22', ...],
    ...
]
```

By default, an active attribute is considered safe and can be massively assigned.
If an attribute should NOT be massively assigned (thus considered unsafe),
please prefix the attribute with an exclamation character (e.g. `'!rank'`).

The default implementation of this method will return all scenarios found in the [`rules()`](/docs/api/yii/base/model/index.md#method-rules)
declaration. A special scenario named [`SCENARIO_DEFAULT`](/docs/api/yii/base/model/index.md#const-SCENARIO_DEFAULT) will contain all attributes
found in the [`rules()`](/docs/api/yii/base/model/index.md#method-rules). Each scenario will be associated with the attributes that
are being validated by the validation rules that apply to the scenario.

**Returns**

`array<string, string[]>`: A list of scenarios and the corresponding active attributes.

### setAttributes() <span id="method-setAttributes"></span>

```php
public function setAttributes(array<string, mixed> $values, bool $safeOnly = true): mixed
```

Sets the attribute values in a massive way.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$values` | `array<string, mixed>` | Attribute values (name => value) to be assigned to the model. |
| `$safeOnly` | `bool` | Whether the assignments should only be done to the safe attributes. A safe attribute is one that is associated with a validation rule in the current [`$scenario`](/docs/api/yii/base/model/index.md#property-scenario). |

**Returns**

`mixed`

**See also**

- [`safeAttributes()`](/docs/api/yii/base/model/index.md#method-safeAttributes)
- [`attributes()`](/docs/api/yii/base/model/index.md#method-attributes)

### setScenario() <span id="method-setScenario"></span>

```php
public function setScenario(string $value): mixed
```

Sets the scenario for the model.

Note that this method does not check if the scenario exists or not.
The method [`validate()`](/docs/api/yii/base/model/index.md#method-validate) will perform this check.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$value` | `string` | The scenario that this model is in. |

**Returns**

`mixed`

### validate() <span id="method-validate"></span>

```php
public function validate(string[]|string|null $attributeNames = null, bool $clearErrors = true): bool
```

Performs the data validation.

This method executes the validation rules applicable to the current [`$scenario`](/docs/api/yii/base/model/index.md#property-scenario).
The following criteria are used to determine whether a rule is currently applicable:

- the rule must be associated with the attributes relevant to the current scenario;
- the rules must be effective for the current scenario.

This method will call [`beforeValidate()`](/docs/api/yii/base/model/index.md#method-beforeValidate) and [`afterValidate()`](/docs/api/yii/base/model/index.md#method-afterValidate) before and
after the actual validation, respectively. If [`beforeValidate()`](/docs/api/yii/base/model/index.md#method-beforeValidate) returns false,
the validation will be cancelled and [`afterValidate()`](/docs/api/yii/base/model/index.md#method-afterValidate) will not be called.

Errors found during the validation can be retrieved via [`getErrors()`](/docs/api/yii/base/model/index.md#method-getErrors),
[`getFirstErrors()`](/docs/api/yii/base/model/index.md#method-getFirstErrors) and [`getFirstError()`](/docs/api/yii/base/model/index.md#method-getFirstError).

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$attributeNames` | `string[]\|string\|null` | Attribute name or list of attribute names that should be validated. If this parameter is empty, it means any attribute listed in the applicable validation rules should be validated. |
| `$clearErrors` | `bool` | Whether to call [`clearErrors()`](/docs/api/yii/base/model/index.md#method-clearErrors) before performing validation |

**Returns**

`bool`: Whether the validation is successful without any error.

**Throws**

- [`InvalidArgumentException`](/docs/api/yii/base/invalidargumentexception/index.md): if the current scenario is unknown.

### validateMultiple() <span id="method-validateMultiple"></span>

```php
public static function validateMultiple(array $models, array|null $attributeNames = null): bool
```

Validates multiple models.

This method will validate every model. The models being validated may
be of the same or different types.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$models` | `array` | The models to be validated |
| `$attributeNames` | `array\|null` | List of attribute names that should be validated. If this parameter is empty, it means any attribute listed in the applicable validation rules should be validated. |

**Returns**

`bool`: Whether all models are valid. False will be returned if one or multiple models have validation error.