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    The ReflectionProperty class

    (PHP 5, PHP 7, PHP 8)

    Introduction

    The ReflectionProperty class reports information about class properties.

    Class synopsis

    class ReflectionProperty implements Reflector {
    /* Constants */
    public const int IS_STATIC;
    public const int IS_READONLY;
    public const int IS_PUBLIC;
    public const int IS_PROTECTED;
    public const int IS_PRIVATE;
    public const int IS_ABSTRACT;
    public const int IS_PROTECTED_SET;
    public const int IS_PRIVATE_SET;
    public const int IS_VIRTUAL;
    public const int IS_FINAL;
    /* Properties */
    public string $name;
    public string $class;
    /* Methods */
    public __construct(object|string $class, string $property)
    private __clone(): void
    public static export(mixed $class, string $name, bool $return = ?): string
    public getAttributes(?string $name = null, int $flags = 0): array
    public getDeclaringClass(): ReflectionClass
    public getDefaultValue(): mixed
    public getDocComment(): string|false
    public getModifiers(): int
    public getName(): string
    public getType(): ?ReflectionType
    public getValue(?object $object = null): mixed
    public hasDefaultValue(): bool
    public hasType(): bool
    public isDefault(): bool
    public isInitialized(?object $object = null): bool
    public isLazy(object $object): bool
    public isPrivate(): bool
    public isPromoted(): bool
    public isProtected(): bool
    public isPublic(): bool
    public isReadOnly(): bool
    public isStatic(): bool
    public setAccessible(bool $accessible): void
    public setRawValueWithoutLazyInitialization(object $object, mixed $value): void
    public setValue(object $object, mixed $value): void
    public skipLazyInitialization(object $object): void
    public __toString(): string
    }

    Properties

    name

    Name of the property. Read-only, throws ReflectionException in attempt to write.

    class

    Name of the class where the property is defined. Read-only, throws ReflectionException in attempt to write.

    Predefined Constants

    ReflectionProperty Modifiers

    ReflectionProperty::IS_STATIC int

    Indicates static properties. Prior to PHP 7.4.0, the value was 1.

    ReflectionProperty::IS_READONLY int

    Indicates readonly properties. Available as of PHP 8.1.0.

    ReflectionProperty::IS_PUBLIC int

    Indicates public properties. Prior to PHP 7.4.0, the value was 256.

    ReflectionProperty::IS_PROTECTED int

    Indicates protected properties. Prior to PHP 7.4.0, the value was 512.

    ReflectionProperty::IS_PRIVATE int

    Indicates private properties. Prior to PHP 7.4.0, the value was 1024.

    ReflectionProperty::IS_ABSTRACT int
    Indicates the property is abstract. Available as of PHP 8.4.0.
    ReflectionProperty::IS_PROTECTED_SET int
    Available as of PHP 8.4.0.
    ReflectionProperty::IS_PRIVATE_SET int
    Available as of PHP 8.4.0.
    ReflectionProperty::IS_VIRTUAL int
    Available as of PHP 8.4.0.
    ReflectionProperty::IS_FINAL int
    Indicates the property is final. Available as of PHP 8.4.0.

    Note:

    The values of these constants may change between PHP versions. It is recommended to always use the constants and not rely on the values directly.

    Changelog

    Version Description
    8.4.0 The class constants are now typed.
    8.4.0 Added ReflectionProperty::IS_VIRTUAL, ReflectionProperty::IS_PRIVATE_SET, ReflectionProperty::IS_PROTECTED_SET, ReflectionProperty::IS_ABSTRACT, and ReflectionProperty::IS_FINAL.
    8.0.0 ReflectionProperty::export() was removed.

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    User Contributed Notes 1 note

    up
    9
    rasmus at mindplay dot dk
    14 years ago
    I think a more accurate explanation is this:

    The Reflection classes are designed to reflect upon the source code of an application, not on any runtime information.

    I think you misunderstand the ReflectionProperty constructor in your example above. The fact that it accepts an object as argument is just a convenience feature - you are actually inspecting the class of that object, not the object itself, so it's basically equivalent to:

    <?php

    // works fine
    $Reflection = new ReflectionProperty(get_class($a), 'a');

    // throws exception
    $Reflection = new ReflectionProperty(get_class($a), 'foo');

    ?>

    Getting the class of the object you're passing in is implied, since inspecting a defined property is the purpose of this class.

    In your example, $a->foo is a dynamic member - it is not defined as a member of class, so there is no defining class reference, line number, default value, etc. - which means, there is nothing to reflect upon.

    Clearly this very useful library could use some real documentation...
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