jquery在线链接地址
https://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.jshttps://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.jshttps://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.jshttps://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.jshttps://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.jshttps://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js