(PHP 4, PHP 5, PHP 7)
func_get_arg — Return an item from the argument list
func_get_arg ( int $arg_num ) : mixed
Gets the specified argument from a user-defined function's argument list.
This function may be used in conjunction with func_get_args() and func_num_args() to allow user-defined functions to accept variable-length argument lists.
arg_num
The argument offset. Function arguments are counted starting from zero.
Returns the specified argument, or false
on error.
Generates a warning if called from outside of a user-defined function, or if arg_num
is greater than the number of arguments actually passed.
Example #1 func_get_arg() 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"; } } foo(1, 2, 3); ?>
The above example will output:
Number of arguments: 3 Second argument is: 2
Example #2 func_get_arg() example before and after PHP 5.3
test.php <?php function foo() { include './fga.inc'; } foo('First arg', 'Second arg'); ?> fga.inc <?php $arg = func_get_arg(1); var_export($arg); ?>
Output previous to PHP 5.3:
'Second arg'
Output in PHP 5.3 and later:
Warning: func_get_arg(): Called from the global scope - no function context in /home/torben/Desktop/code/ml/fga.inc on line 3 false
Example #3 func_get_arg() example of byref and byval arguments
<?php function byVal($arg) { echo 'As passed : ', var_export(func_get_arg(0)), PHP_EOL; $arg = 'baz'; echo 'After change : ', var_export(func_get_arg(0)), PHP_EOL; } function byRef(&$arg) { echo 'As passed : ', var_export(func_get_arg(0)), PHP_EOL; $arg = 'baz'; echo 'After change : ', var_export(func_get_arg(0)), PHP_EOL; } $arg = 'bar'; byVal($arg); byRef($arg); ?>
Output of the above example in PHP 7:
Output of the above example in PHP 5:
Note:
Because this function depends on the current scope to determine parameter details, it cannot be used as a function parameter in versions prior to 5.3.0. If this value must be passed, the results should be assigned to a variable, and that variable should be passed.
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.
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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.func-get-arg.php