php函数调用方法 call_user_func_array()

<?php
namespace jia;
function foobar($arg1, $arg2)
{
    echo __FUNCTION__." got $arg1, $arg2. ";
}
$func = function($arg)
{
    echo "hello, $arg";
};
class foo
{
    function bar($arg3, $arg4)
    {
        echo __FUNCTION__." got $arg3, $arg4. ";
    }
}
foobar("leo", "jia");
$afoo = new foo();
$afoo->bar("hello", "kityy");
call_user_func_array("jia\\foobar",array("jia","yusheng"));\
call_user_func_array(__NAMESPACE__."\\foobar",array("wang","xiaoer"));
call_user_func_array(array($afoo,"bar"),array("li","dazhao"));
call_user_func_array(__NAMESPACE__."\\foo::bar",array("tan","sitong"));
call_user_func_array(array("jia\\foo","bar"),array("kang","youwei"));
call_user_func_array($func,array("world"));
?>