请问各位大神一个正则问题

$str = '[[{"id":"","url":"","title":""xxxxxxxxxxxxxxxxxxxxxxx"","thumb":"","description":"","color":"","size":"14px"}]]';
先需要"title":" 开头 以","thumb" 结尾  替换"xxxxxxxxxxxxxxxxxxxxxxx" 为 \"xxxxxxxxxxxxxxxxxxxxxxx\"    请大神们指导指导

回复讨论(解决方案)

看看是不是你想要的结果
preg_replace("/title\":\"\"(.*)\"\",\"thumb/i","title:\"\\\"\\1\\\"\",\"thumb",$str);