我有一个字符串，更具体地说，这个：
a:16:{s:9:"pseudonym";O:16:"SimpleXMLElement":0:{}s:14:"parallel_title";O:16:"SimpleXMLElement":0:{}s:9:"title_var";O:16:"SimpleXMLElement":0:{}s:6:"series";O:16:"SimpleXMLElement":0:{}s:9:"vol_title";O:16:"SimpleXMLElement":0:{}s:9:"reference";O:16:"SimpleXMLElement":0:{}s:10:"bound_with";O:16:"SimpleXMLElement":0:{}s:15:"general_remarks";O:16:"SimpleXMLElement":0:{}s:6:"copies";O:16:"SimpleXMLElement":1:{i:0;s:1:"1";}s:11:"remarks_BPH";O:16:"SimpleXMLElement":0:{}s:3:"ICN";O:16:"SimpleXMLElement":1:{i:0;s:4:"neen";}s:10:"provenance";O:16:"SimpleXMLElement":0:{}s:7:"binding";O:16:"SimpleXMLElement":0:{}s:10:"size_hxwxd";O:16:"SimpleXMLElement":0:{}s:6:"BookID";O:16:"SimpleXMLElement":1:{i:0;s:4:"6271";}s:5:"repro";O:16:"SimpleXMLElement":0:{}}
是否有可能以某种方式解析这个字符串？我需要在列表中显示键和值。我尝试使用json_decode，但它不返回任何内容，即使将第二个参数设置为true：
json_decode($string,true);