If the asynchronous result you're waiting for comes back, make the DOM changes necessary to display it, and then remember that you processed the result.
如果等待的异步结果返回了，对DOM作必要的修改并显示然后再处理结果。
2
Ajax, as the Web development community well knows, allows you to make asynchronous auxiliary requests to the server and display the resulting output directly on the Web page (see Figure 4).