Question

我在经典的asp应用程序中使用ajax调用来执行存储过程但我不想等到存储过程运行（存储过程需要大约5-10分钟才能完成。） Ajax必须调用存储过程并需要立即返回我希望Ajax调用不要等待响应。

这是我的代码段：

1)  $.ajax({  
  type: "POST",  
  url: "runstoredprocedure.asp",  
});    
2)  setInterval(function(){  jQuery("#list").trigger("reloadGrid"); },10000);

这是我正在使用的两个ajax调用。第一个跑步约5-7分钟。第二个没有开始，直到第一个完成。但是我立刻需要拨打第二个ajax电话。

任何人都可以帮我解决这个问题。

Answer 1

javascript会将请求作为不同线程的一部分触发，并且会立即执行ajax调用之后的任何代码。说过一个关于JS异步的误解：

People take for granted that because it’s asynchronous, it’s a thread. They are partially right. There must be a thread created by the browser to keep the javascript running while it makes a request to the server. It’s internal and you don’t have access to that thread. But, the callback function called when the server responds to the ajax request is not in a thread.

I’ll explain clearer. If javascript runs some code that takes 5 seconds to execute and an ajax response arrives at 2 seconds, it will take 3 seconds before it will be executed (before the callback function is called). That’s because javascript itself doesn’t create a thread to execute the ajax response from the server and simply waits that all executions are terminated before starting a new one.

So if you’re running a lot of ajax requests simultaneously, you might get some weird behavior because they will all wait one on another before executing themselves.

最后一句话与你的事业有关。

摘自博客：http://www.javascriptkata.com/2007/06/04/ajax-and-javascript-dont-use-threads/

有趣的阅读：http://www.javascriptkata.com/2007/06/12/ajax-javascript-and-threads-the-final-truth/

Answer 2

AJAX默认是异步的（它是所有javascript库中的默认选项）。例如，在jQuery中：

$.ajax({
  url: url,
  data: data,
  success: success,
  dataType: dataType
});

你取得了成功，需要回调。当您的操作完成后，将调用回调。 jQuery会立即返回。

Ajax调用不应该等待响应

2 个答案: