<?php

function foobar($arg1, $arg2)
{
    echo __FUNCTION__ . " got $arg1 and $arg2\n";
}

class foo
{
    function bar($arg1, $arg2)
    {
        echo __METHOD__ . " got $arg1 and $arg2\n";
    }
}

call_user_func_array('foobar', ['one', 'tow']);

$foo = new foo;
call_user_func_array([$foo, 'bar'], ['one', 'two']);