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    La clase ReflectionParameter

    (PHP 5, PHP 7, PHP 8)

    Introducción

    La clase ReflectionParameter recupera información sobre los parámetros de la función o del método.

    Para hacer la introspección a los parámetros de la función, primero se crea una instancia de ReflectionFunction o de ReflectionMethod, y entonces se utiliza su método ReflectionFunctionAbstract::getParameters() para obtener un array de los parámetros.

    Sinopsis de la Clase

    class ReflectionParameter implements Reflector {
    /* Propiedades */
    public $name;
    /* Métodos */
    public allowsNull(): bool
    public canBePassedByValue(): bool
    final private __clone(): void
    public __construct(callable $function, mixed $parameter)
    public static export(string $function, string $parameter, bool $return = ?): string
    public getAttributes(?string $name = null, int $flags = 0): array
    public getClass(): ReflectionClass
    public getDeclaringClass(): ReflectionClass
    public getDeclaringFunction(): ReflectionFunctionAbstract
    public getDefaultValue(): mixed
    public getDefaultValueConstantName(): string
    public getName(): string
    public getPosition(): int
    public getType(): ?ReflectionType
    public hasType(): bool
    public isArray(): bool
    public isCallable(): bool
    public isDefaultValueAvailable(): bool
    public isDefaultValueConstant(): bool
    public isOptional(): bool
    public isPassedByReference(): bool
    public isPromoted(): bool
    public isVariadic(): bool
    public __toString(): string
    }

    Propiedades

    name

    Nombre de el parámetro. De sólo lectura, lanza una ReflectionException en el intento de escribir.

    Tabla de contenidos

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    User Contributed Notes 4 notes

    up
    7
    fgm at riff dot org
    16 years ago
    The note about the signature of the ReflectionParameter constructor is actually incomplete, at least in 5.2.5: it is possible to use an integer for the second parameter, and the constructor will use it to return the n-th parameter.

    This allows you to obtain proper ReflectionParameter objects even when documenting code from extensions which (strangely enough) define several parameters with the same name. The string-based constructor always returns the first parameter with the matching name, whereas the integer-based constructor correctly returns the n-th parameter.

    So, in short, this works:
    <?php
    // supposing the extension defined something like:
    // Some_Class::someMethod($a, $x, $y, $x, $y)
    $p = new ReflectionParameter(array('Some_Class', 'someMethod'), 4);
    // returns the last parameter, whereas
    $p = new ReflectionParameter(array('Some_Class', 'someMethod'), 'y');
    // always returns the first $y at position 2
    ?>
    up
    3
    killgecNOFSPAM at gmail dot com
    17 years ago
    Signature of constructor of ReflectionParameter correctly is:

    public function __construct(array/string $function, string $name);

    where $function is either a name of a global function, or a class/method name pair.
    up
    1
    massimo at mmware dot it
    17 years ago
    I found these limitations using class ReflectionParameter from ReflectionFunction with INTERNAL FUNCTIONS (eg print_r, str_replace, ... ) :

    1. parameter names don't match with manual: (try example 19.35 with arg "call_user_func" )
    2. some functions (eg PCRE function, preg_match etc) have EMPTY parameter names
    3. calling getDefaultValue on Parameters will result in Exception "Cannot determine default value for internal functions"
    up
    0
    rasmus at mindplay dot dk
    1 year ago
    There are so many parameter modes now, and I needed to know exactly what `ReflectionParameter` is going to return, so I wrote a little test-script - you can find the script and results in a table here:

    https://gist.github.com/mindplay-dk/082458088988e32256a827f9b7491e17
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