(PHP 4, PHP 5, PHP 7)
func_get_arg — Return an item from the argument list
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.
버전 | 설명 |
---|---|
5.3.0 | This function can now be used in parameter lists. |
5.3.0 |
If this function is called from the outermost scope of a file
which has been included by calling include
or require from within a function in the
calling file, it now generates a warning and returns FALSE .
|
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);
?>
위 예제의 출력:
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:
이 함수는 인수를 현재 영역(scope)에 의존하기 때문에, 함수의 인수로 사용할 수 없습니다. 이 값을 함수에 넘겨야 한다면, 결과값을 변수에 할당하여 그 변수로 넘겨야 합니다.
Note:
인수가 참조로 전달되면, 인수에 대한 변화는 이 함수가 반환하는 값에 영향을 줍니다.
Note: This function returns a copy of the passed arguments only, and does not account for default (non-passed) arguments.