(PHP 4, PHP 5)
func_num_args — Returns the number of arguments passed to the function
Gets the number of arguments passed to the function.
This function may be used in conjunction with func_get_arg() and func_get_args() to allow user-defined functions to accept variable-length argument lists.
Returns the number of arguments passed into the current user-defined function.
| 版本 | 说明 |
|---|---|
| 5.3.0 | This function can now be used in parameter lists. |
| 5.3.0 | If this function is called from the outtermost 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 -1. |
Generates a warning if called from outside of a user-defined function.
Example #1 func_num_args() example
<?php
function foo()
{
$numargs = func_num_args();
echo "Number of arguments: $numargs\n";
}
foo(1, 2, 3);
?>
上例将输出：
Number of arguments: 3
Example #2 func_num_args() example before and after PHP 5.3
test.php
<?php
function foo() {
include './fga.inc';
}
foo('First arg', 'Second arg');
?>
fga.php
<?php
$num_args = func_num_args();
var_export($num_args);
?>
Output previous to PHP 5.3:
2
Output in PHP 5.3 and later:
Warning: func_num_args(): Called from the global scope - no function context in /home/torben/Desktop/code/ml/fga.inc on line 3 -1
Note: Because this function depends on the current scope to determine parameter details, it cannot be used as a function parameter. If this value must be passed, the results should be assigned to a variable, and that variable should be passed.