int func_num_args(void );Returns the number of arguments passed into the current user-defined function. func_num_args will generate a warning if called from outside of a function definition.
<?php
function foo() {
$numargs = func_num_args();
echo "Number of arguments: $numargs\n";
}
foo( 1, 2, 3 ); // Prints 'Number of arguments: 3'
?>
func_num_args may be used in conjunction with func_get_arg and func_get_args to allow user-defined functions to accept variable-length argument lists.
注意: This function was added in PHP 4.