为页面上的所有AJAX请求添加“钩子”

I'd like to know if it's possible to "hook" into every single AJAX request (either as it's about to get sent, or on events) and perform an action. At this point I'm assuming that there are other third-party scripts on the page. Some of these might use jQuery, while others do not. Is this possible?I'd like to know if it's possible to "hook" int