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Negative

5.2 version
Maintained Unmaintained

Negative

Validates that a value is a negative number. Zero is neither positive nor negative, so you must use NegativeOrZero if you want to allow zero as value.

Applies to property or method
Options
Class Symfony\Component\Validator\Constraints\Negative
Validator Symfony\Component\Validator\Constraints\LesserThanValidator

Basic Usage

The following constraint ensures that the withdraw of a bank account TransferItem is a negative number (lesser than zero):

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    // src/Entity/TransferItem.php
    namespace App\Entity;
    
    use Symfony\Component\Validator\Constraints as Assert;
    
    class TransferItem
    {
        /**
         * @Assert\Negative
         */
        protected $withdraw;
    }
    
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    # config/validator/validation.yaml
    App\Entity\TransferItem:
        properties:
            withdraw:
                - Negative: ~
    
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    <!-- config/validator/validation.xml -->
    <?xml version="1.0" encoding="UTF-8" ?>
    <constraint-mapping xmlns="http://symfony.com/schema/dic/constraint-mapping"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="http://symfony.com/schema/dic/constraint-mapping https://symfony.com/schema/dic/constraint-mapping/constraint-mapping-1.0.xsd">
    
        <class name="App\Entity\TransferItem">
            <property name="withdraw">
                <constraint name="Negative"></constraint>
            </property>
        </class>
    </constraint-mapping>
    
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    // src/Entity/TransferItem.php
    namespace App\Entity;
    
    use Symfony\Component\Validator\Constraints as Assert;
    use Symfony\Component\Validator\Mapping\ClassMetadata;
    
    class TransferItem
    {
        public static function loadValidatorMetadata(ClassMetadata $metadata)
        {
            $metadata->addPropertyConstraint('withdraw', new Assert\Negative());
        }
    }
    

Available Options

groups

type: array | string

It defines the validation group or groups this constraint belongs to. Read more about validation groups.

message

type: string default: This value should be negative.

The default message supplied when the value is not less than zero.

You can use the following parameters in this message:

Parameter Description
{{ compared_value }} Always zero
{{ compared_value_type }} The expected value type
{{ value }} The current (invalid) value

payload

type: mixed default: null

This option can be used to attach arbitrary domain-specific data to a constraint. The configured payload is not used by the Validator component, but its processing is completely up to you.

For example, you may want to use several error levels to present failed constraints differently in the front-end depending on the severity of the error.

This work, including the code samples, is licensed under a Creative Commons BY-SA 3.0 license.