SimpleXML objects in PHP cannot be serialized ____php

It is very convenient for a friend who is sure to deal with XML frequently to use simplexml_load_string, and he turns XML into an object. But if you want to serialize the object and cache it, be careful. There is no problem writing cache, but error reading cache, the error is "Node no longer exists in xxxx.php on line 15". The error occurs because of the deserialization of the SimpleXML object. It's probably a bug in PHP.

The following code can verify my experience and be careful when serializing SimpleXML objects later. ? Php
$data = <<< XML
? XML version = ' 1.0 '?>
< articles >
< article >
< title > Wang Kaiyuan PK Bill title >
Article >
Articles >
XML;
$xml = simplexml_load_string ($data);
$str = serialize ($xml);
echo "$str";
$new _xml = unserialize ($STR);
Echo Serialize ($new _xml). " " ;
?>