how to dynamically check number of arguments of a function in php

Question

how can I check at runtime home many parameters a method or a function have in PHP.

example

class foo {
   function bar ( arg1, arg2 ){
    .....
   }
}

I will need to know if there is a way to run something like

get_func_arg_number ( "foo", "bar" )

and the result to be

2

Answer 1

You're looking for the reflection capabilities in PHP5 -- documentation here.

Specifically, look at the ReflectionFunction and ReflcetionMethod classes.

Answer 2

I believe you are looking for func_num_args()

http://us3.php.net/manual/en/function.func-num-args.php

Answer 3

You need to use reflection to do that.

$method = new ReflectionMethod('foo', 'bar');
$num = $method->getNumberOfParameters();

Answer 4

Reflection is what you're after here

class foo {
   function bar ( $arg1, $arg2 ){

   }
}
$ReflectionFoo = new ReflectionClass('foo');
echo $ReflectionFoo->getMethod('bar')->getNumberOfParameters();