采用任何方式 data_response 之外 $。员额（）？

这是的code我用一部分：

This is part of the code I use:

$.post('do.php', { OP: "news_search", category: cat_id },
    function(data_response){
        var response = data_response; //I need to access this variable outside of $.post()
    }
}, "json");

console.log(response); //response is not defined, is what I get for now

更新

请问有没有办法让这种反应可在全球范围的？

UPDATE

Is there no way of getting that response available globally?

推荐答案

没有; $。交异步执行，所以当你调用的console.log ，AJAX请求仍在运行，并且有不还产生了一个响应。这是回调函数的宗旨：为code要运行的在的请求已完成。如果移动的console.log 进入回调函数，它应该工作：

No; $.post executes asynchronously, so when you call console.log, the AJAX request is still running and hasn't yet yielded a response. This is the purpose of the callback function: to provide code to be run after the request has completed. If you move console.log into the callback function, it should work:

$.post('do.php', { OP: "news_search", category: cat_id },
    function(data_response){
        var response = data_response; //I need to access this variable outside of $.post()
        console.log(response);
    }
}, "json");

更新：如果您想响应数据是全局可用，您可以像这样在全球范围内声明的变量：

Update: If you want the response data to be globally available, you can declare the variable in the global scope like so:

var response = null;
$.post('do.php', { OP: "news_search", category: cat_id },
    function(data_response){
        response = data_response;
        console.log(response);
    }
}, "json");

当然，在其中可以肯定的是响应拥有国内唯一的上下文 实际上已被填充了一个值是在供给到回调函数 $交行之后响应= data_response; 。如果你想使用它 在脚本中任何其他阶段，那么你就必须先检查它的价值; 是这样的：

Of course, the only context in which you can be sure that response has actually been populated with a value is in the callback function supplied to $.post after the line response = data_response;. If you want to use it at any other stage in the script then you'll have to check its value first; something like this:

if (response !== null)
{
    console.log(response);
}

要知道，如果你把它直接在此之后code不会做任何事情 。在 $交通话;如果它执行时，就只能用后POST请求完成后，在其他一些异步回调（可能是一个用户界面交互某种情况下）。

Just be aware that this code won't do anything if you put it straight after the $.post call; it'll only be useful if it's executed after the POST request has finished, in some other asynchronous callback (perhaps a UI interaction event of some kind).