php获取rar文件里面的内容，输出来如何解析？

最近有一个需求：将rar压缩文件里面的文件名、大小获取出来，解析成json输出来；
查阅了无数资料，得知添加php_rar.dll(如果是zip的话，就添加php_zip.dll扩展)，最后通过程序得到rar的相关内容，但对里面获取到的内容格式不知道怎么解析成json，求大神指点一二。

$rar_file = rar_open('222.rar') or die("Failed to open Rar archive");

$entries_list = rar_list($rar_file);

header('Content-Type: text/plain');
print_r($entries_list);

得到数据如下：
Array
(
[0] => RarEntry Object
(
[rarfile:RarEntry:private] => RarArchive Object
(
)

        [position:RarEntry:private] => 0
        [name:RarEntry:private] => tar.php
        [unpacked_size:RarEntry:private] => 64332
        [packed_size:RarEntry:private] => 11726
        [host_os:RarEntry:private] => 2
        [file_time:RarEntry:private] => 2012-07-09 23:47:06
        [crc:RarEntry:private] => 69e1487f
        [attr:RarEntry:private] => 128
        [version:RarEntry:private] => 29
        [method:RarEntry:private] => 51
        [flags:RarEntry:private] => 32928
    )

[1] => RarEntry Object
    (
        [rarfile:RarEntry:private] => RarArchive Object
            (
            )

        [position:RarEntry:private] => 1
        [name:RarEntry:private] => upload.php
        [unpacked_size:RarEntry:private] => 2461
        [packed_size:RarEntry:private] => 1033
        [host_os:RarEntry:private] => 2
        [file_time:RarEntry:private] => 2012-07-09 23:47:06
        [crc:RarEntry:private] => ecc4a20d
        [attr:RarEntry:private] => 128
        [version:RarEntry:private] => 29
        [method:RarEntry:private] => 51
        [flags:RarEntry:private] => 32928
    )

[2] => RarEntry Object
    (
        [rarfile:RarEntry:private] => RarArchive Object
            (
            )

        [position:RarEntry:private] => 2
        [name:RarEntry:private] => urlupload.php
        [unpacked_size:RarEntry:private] => 1877
        [packed_size:RarEntry:private] => 864
        [host_os:RarEntry:private] => 2
        [file_time:RarEntry:private] => 2012-07-09 23:47:06
        [crc:RarEntry:private] => 44a999a9
        [attr:RarEntry:private] => 128
        [version:RarEntry:private] => 29
        [method:RarEntry:private] => 51
        [flags:RarEntry:private] => 32928
    )

[3] => RarEntry Object
    (
        [rarfile:RarEntry:private] => RarArchive Object
            (
            )

        [position:RarEntry:private] => 3
        [name:RarEntry:private] => user.php
        [unpacked_size:RarEntry:private] => 402
        [packed_size:RarEntry:private] => 222
        [host_os:RarEntry:private] => 2
        [file_time:RarEntry:private] => 2012-07-09 23:47:06
        [crc:RarEntry:private] => 22db657e
        [attr:RarEntry:private] => 128
        [version:RarEntry:private] => 29
        [method:RarEntry:private] => 51
        [flags:RarEntry:private] => 32928
    )

）

RarEntry Object这是神马意思？

RarEntry就是rar文件里每个压缩的文件

我循环数组之后，得到里面那一串再怎么处理？