如何区分“消息"更新和“回调查询"更新?(电报机器人 API)

对不起，如果我的问题太乱了，我是新来的，所以，欢迎任何建议.

Sorry if my question gets too messy, I'm new here, so, any advice is welcome.

如何区分消息"更新和回调查询"更新?我已经设法制作了一个内联键盘，但是当我使用它时，机器人就挂了，他什么都不回复.我做了一些研究，发现 这个问题，帮助我理解了这个问题，但除此之外别无他法.

How can I differentiate between a 'Message' update and a 'Callback Query' update? I've managed to make an inline keyboard, but when I use it, the bot just hangs, he doesn't reply anything. I did a little bit of research and found this question, which helped me understand the problem, but not much else.

我的机器人现在正在使用这样的东西:

My bot uses something like this right now:

// read incoming info and grab the chatID
$content = file_get_contents("php://input");
$update = json_decode($content, true);
$chatID = $update["message"]["chat"]["id"];

switch($update["message"]["text"]){
    /* insert magic here */
}

所以，这段代码可以处理消息，但不能处理回调查询.如果我想处理它们，我可以使用这样的方法(基于另一个问题的答案):

So, this code can handle Messages, but not CallbackQueries. If I wantew to handle them, I could use something like this (based on the other question's answer):

$callback_query = $update["callback_query"]
/* same as above */

但是我如何检查它是消息还是回调查询?

But how can I check whether it is a message or a callback query?