PHP: func_get_args - Manual (original) (raw)

(PHP 4, PHP 5, PHP 7, PHP 8)

func_get_args — Returns an array comprising a function's argument list

Description

func_get_args(): array

This function may be used in conjunction with func_get_arg() and func_num_args() to allow user-defined functions to accept variable-length argument lists.

Parameters

This function has no parameters.

Return Values

Returns an array in which each element is a copy of the corresponding member of the current user-defined function's argument list.

Errors/Exceptions

Generates a warning if called from outside of a user-defined function.

Examples

Example #1 func_get_args() example

<?php function foo() { $numargs = func_num_args(); echo "Number of arguments: $numargs \n"; if ($numargs >= 2) { echo "Second argument is: " . func_get_arg(1) . "\n"; } $arg_list = func_get_args(); for ($i = 0; <math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>i</mi><mo><</mo></mrow><annotation encoding="application/x-tex">i < </annotation></semantics></math>i<numargs; $i++) { echo "Argument <math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>i</mi><mi>i</mi><mi>s</mi><mo>:</mo><mi mathvariant="normal">"</mi><mi mathvariant="normal">.</mi></mrow><annotation encoding="application/x-tex">i is: " . </annotation></semantics></math>iis:".arg_list[$i] . "\n"; } }foo(1, 2, 3); ?>

The above example will output:

Number of arguments: 3 Second argument is: 2 Argument 0 is: 1 Argument 1 is: 2 Argument 2 is: 3

Example #2 func_get_args() example of byref and byval arguments

`<?php
function byVal($arg) {
echo 'As passed : ', var_export(func_get_args()), PHP_EOL;
$arg = 'baz';
echo 'After change : ', var_export(func_get_args()), PHP_EOL;
}

function

byRef(&$arg) {
echo 'As passed : ', var_export(func_get_args()), PHP_EOL;
$arg = 'baz';
echo 'After change : ', var_export(func_get_args()), PHP_EOL;
}$arg = 'bar';
byVal($arg);
byRef($arg);
?>`

The above example will output:

As passed : array (
0 => 'bar',
)
After change : array (
0 => 'baz',
)
As passed : array (
0 => 'bar',
)
After change : array (
0 => 'baz',
)

Notes

Note:

As of PHP 8.0.0, the func_*() family of functions is intended to be mostly transparent with regard to named arguments, by treating the arguments as if they were all passed positionally, and missing arguments are replaced with their defaults. This function ignores the collection of unknown named variadic arguments. Unknown named arguments which are collected can only be accessed through the variadic parameter.

Note:

If the arguments are passed by reference, any changes to the arguments will be reflected in the values returned by this function. As of PHP 7 the current values will also be returned if the arguments are passed by value.

Note: This function returns a copy of the passed arguments only, and does not account for default (non-passed) arguments.

Found A Problem?

cobrattila at gmail dot com ¶

6 years ago

If you want to get the arguments by reference, instead of func_get_args() you can simply use

<?php
function args_byref(&...$args) {
    // Modify the $args array here
}
?>

Credits should go to Markus Malkusch for pointing this out on Stackoverflow.
https://stackoverflow.com/a/29181826/1426064