# DefaultValueValidator

> DefaultValueValidator sets the attribute to be the specified default value.

[API reference](/docs/api/index.md) › [yii](/docs/api/yii/index.md) › [validators](/docs/api/yii/validators/index.md) › DefaultValueValidator

| class | `yii\validators\DefaultValueValidator` |
| --- | --- |
| Extends | [`Validator`](/docs/api/yii/validators/validator/index.md) » [`yii\base\Component`](/docs/api/yii/base/component/index.md) » [`yii\base\BaseObject`](/docs/api/yii/base/baseobject/index.md) |
| Implements | [`yii\base\Configurable`](/docs/api/yii/base/configurable/index.md) |
| Since | 2.0 |
| Source | [`framework/validators/DefaultValueValidator.php`](https://github.com/yiisoft/yii2/blob/22.0/framework/validators/DefaultValueValidator.php#L20) |

DefaultValueValidator sets the attribute to be the specified default value.

DefaultValueValidator is not really a validator. It is provided mainly to allow
specifying attribute default values when they are empty.

## Properties

| Property | Type | Description | Defined by |
| --- | --- | --- | --- |
| <span id="property-attributeNames"></span>[`$attributeNames`](/docs/api/yii/validators/validator/index.md#property-attributeNames) read-only | `array` | Attribute names. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="property-attributes"></span>[`$attributes`](/docs/api/yii/validators/validator/index.md#property-attributes) | `array\|string` | Attributes to be validated by this validator. Default: `[]`. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="property-behaviors"></span>[`$behaviors`](/docs/api/yii/base/component/index.md#property-behaviors) read-only | `array<`[`yii\base\Behavior`](/docs/api/yii/base/behavior/index.md)`<static>>` | List of behaviors attached to this component. | [`yii\base\Component`](/docs/api/yii/base/component/index.md) |
| <span id="property-builtInValidators"></span>[`$builtInValidators`](/docs/api/yii/validators/validator/index.md#property-builtInValidators) static | `array` | List of built-in validators (name => class or configuration) Default: `['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']`. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="property-enableClientValidation"></span>[`$enableClientValidation`](/docs/api/yii/validators/validator/index.md#property-enableClientValidation) | `bool` | Whether to enable client-side validation for this validator. Default: `true`. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="property-except"></span>[`$except`](/docs/api/yii/validators/validator/index.md#property-except) | `array\|string` | Scenarios that the validator should not be applied to. Default: `[]`. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="property-isEmpty"></span>[`$isEmpty`](/docs/api/yii/validators/validator/index.md#property-isEmpty) | `callable\|null` | A PHP callable that replaces the default implementation of [`isEmpty()`](/docs/api/yii/validators/validator/index.md#method-isEmpty). Default: `null`. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="property-message"></span>[`$message`](/docs/api/yii/validators/validator/index.md#property-message) | `string\|null` | The user-defined error message. Default: `null`. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="property-on"></span>[`$on`](/docs/api/yii/validators/validator/index.md#property-on) | `array\|string` | Scenarios that the validator can be applied to. Default: `[]`. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="property-skipOnEmpty"></span>`$skipOnEmpty` | `bool` | This property is overwritten to be false so that this validator will be applied when the value being validated is empty. Default: `false`. | `DefaultValueValidator` |
| <span id="property-skipOnError"></span>[`$skipOnError`](/docs/api/yii/validators/validator/index.md#property-skipOnError) | `bool` | Whether this validation rule should be skipped if the attribute being validated already has some validation error according to some previous rules. Default: `true`. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="property-validationAttributes"></span>[`$validationAttributes`](/docs/api/yii/validators/validator/index.md#property-validationAttributes) read-only | `array\|null` | List of attribute names. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| [`$value`](#property-value) | `mixed` | The default value or an anonymous function that returns the default value which will be assigned to the attributes being validated if they are empty. Default: `null`. | `DefaultValueValidator` |
| <span id="property-when"></span>[`$when`](/docs/api/yii/validators/validator/index.md#property-when) | `callable\|null` | A PHP callable whose return value determines whether this validator should be applied. Default: `null`. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="property-whenClient"></span>[`$whenClient`](/docs/api/yii/validators/validator/index.md#property-whenClient) | `string\|null` | A JavaScript function name whose return value determines whether this validator should be applied on the client-side. Default: `null`. | [`Validator`](/docs/api/yii/validators/validator/index.md) |

## Methods

| Method | Description | Defined by |
| --- | --- | --- |
| <span id="method-__construct"></span>[`__construct()`](/docs/api/yii/base/baseobject/index.md#method-__construct) | Constructor. | [`yii\base\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. | [`yii\base\Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-__clone"></span>[`__clone()`](/docs/api/yii/base/component/index.md#method-__clone) | This method is called after the object is created by cloning an existing one. | [`yii\base\Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-__get"></span>[`__get()`](/docs/api/yii/base/component/index.md#method-__get) | Returns the value of a component property. | [`yii\base\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. | [`yii\base\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. | [`yii\base\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. | [`yii\base\Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-addError"></span>[`addError()`](/docs/api/yii/validators/validator/index.md#method-addError) | Adds an error about the specified attribute to the model object. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="method-attachBehavior"></span>[`attachBehavior()`](/docs/api/yii/base/component/index.md#method-attachBehavior) | Attaches a behavior to this component. | [`yii\base\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. | [`yii\base\Component`](/docs/api/yii/base/component/index.md) |
| <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. | [`yii\base\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. | [`yii\base\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. | [`yii\base\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. | [`yii\base\BaseObject`](/docs/api/yii/base/baseobject/index.md) |
| <span id="method-clientValidateAttribute"></span>[`clientValidateAttribute()`](/docs/api/yii/validators/validator/index.md#method-clientValidateAttribute) | Returns the JavaScript needed for performing client-side validation. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="method-createValidator"></span>[`createValidator()`](/docs/api/yii/validators/validator/index.md#method-createValidator) static | Creates a validator object. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="method-detachBehavior"></span>[`detachBehavior()`](/docs/api/yii/base/component/index.md#method-detachBehavior) | Detaches a behavior from the component. | [`yii\base\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. | [`yii\base\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. | [`yii\base\Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-getAttributeNames"></span>[`getAttributeNames()`](/docs/api/yii/validators/validator/index.md#method-getAttributeNames) | Returns cleaned attribute names without the `!` character at the beginning. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="method-getBehavior"></span>[`getBehavior()`](/docs/api/yii/base/component/index.md#method-getBehavior) | Returns the named behavior object. | [`yii\base\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. | [`yii\base\Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-getClientOptions"></span>[`getClientOptions()`](/docs/api/yii/validators/validator/index.md#method-getClientOptions) | Returns the client-side validation options. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="method-getFormattedClientMessage"></span>[`getFormattedClientMessage()`](/docs/api/yii/validators/validator/index.md#method-getFormattedClientMessage) | Returns the formatted validation message for client-side validation. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="method-getValidationAttributes"></span>[`getValidationAttributes()`](/docs/api/yii/validators/validator/index.md#method-getValidationAttributes) | Returns a list of attributes this validator applies to. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <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. | [`yii\base\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. | [`yii\base\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. | [`yii\base\Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-init"></span>[`init()`](/docs/api/yii/validators/validator/index.md#method-init) | Initializes the object. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="method-isActive"></span>[`isActive()`](/docs/api/yii/validators/validator/index.md#method-isActive) | Returns a value indicating whether the validator is active for the given scenario and attribute. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="method-isEmpty"></span>[`isEmpty()`](/docs/api/yii/validators/validator/index.md#method-isEmpty) | Checks if the given value is empty. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="method-off"></span>[`off()`](/docs/api/yii/base/component/index.md#method-off) | Detaches an existing event handler from this component. | [`yii\base\Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-on"></span>[`on()`](/docs/api/yii/base/component/index.md#method-on) | Attaches an event handler to an event. | [`yii\base\Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-trigger"></span>[`trigger()`](/docs/api/yii/base/component/index.md#method-trigger) | Triggers an event. | [`yii\base\Component`](/docs/api/yii/base/component/index.md) |
| <span id="method-validate"></span>[`validate()`](/docs/api/yii/validators/validator/index.md#method-validate) | Validates a given value. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| [`validateAttribute()`](#method-validateAttribute) | Validates a single attribute. | `DefaultValueValidator` |
| <span id="method-validateAttributes"></span>[`validateAttributes()`](/docs/api/yii/validators/validator/index.md#method-validateAttributes) | Validates the specified object. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="method-formatMessage"></span>[`formatMessage()`](/docs/api/yii/validators/validator/index.md#method-formatMessage) protected | Formats a mesage using the I18N, or simple strtr if `\Yii::$app` is not available. | [`Validator`](/docs/api/yii/validators/validator/index.md) |
| <span id="method-validateValue"></span>[`validateValue()`](/docs/api/yii/validators/validator/index.md#method-validateValue) protected | Validates a value. | [`Validator`](/docs/api/yii/validators/validator/index.md) |

## Property details

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

```php
public mixed $value = null
```

The default value or an anonymous function that returns the default value which will be assigned to the attributes being validated if they are empty.

The signature of the anonymous function
should be as follows,

```
function($model, $attribute) {
    // compute value
    return $value;
}
```

## Method details

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

```php
public function validateAttribute(mixed $model, mixed $attribute): mixed
```

Validates a single attribute.

Child classes must implement this method to provide the actual validation logic.

**Parameters**

| Parameter | Type | Description |
| --- | --- | --- |
| `$model` | `mixed` | The data model to be validated |
| `$attribute` | `mixed` | The name of the attribute to be validated. |

**Returns**

`mixed`