javascript 如何在onbeforeunload上执行ajax函数？
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How to execute ajax function onbeforeunload?
提问by matheusvmbruno
I'm developing a php/javascript chat.
我正在开发一个 php/javascript 聊天。
When the user logs in, his/her username is inserted in a MySQL table called queue.
This insert returns the mysql_insert_id()that will be stored in a session variable called $_SESSION['CHAT_QUEUE_ID']
当用户登录时，他/她的用户名被插入到名为 的 MySQL 表中queue。此插入返回mysql_insert_id()将存储在名为$_SESSION['CHAT_QUEUE_ID']
I need the MySQL table row to be deleted when the user closes the page.
我需要在用户关闭页面时删除 MySQL 表行。
I tried the following, but without success:
我尝试了以下方法，但没有成功：
js file
js文件
window.onbeforeunload = closeSession;
function closeSession(){
$.ajax({
url: "/chat/process/chat.php",
type: "GET"
});
return "disconnected";
}
chat.php
聊天.php
$delete= "DELETE FROM queue WHERE id = " . $_SESSION['CHAT_QUEUE_ID'];
// query, etc
Is there any way to do this?
有没有办法做到这一点？
回答by StilgarBF
You fire your ajax async (default for jquery - ajax). But the browser won't wait for anything on unload.
您触发 ajax 异步（jquery 的默认设置 - ajax）。但是浏览器不会等待任何卸载。
try setting async : falsein the ajax-settings. But you can never be sure that this will work in all browsers everytime.
尝试async : false在 ajax-settings 中设置。但是您永远无法确定这每次都适用于所有浏览器。
see the comment here: http://api.jquery.com/unload/#dsq-comment-body-132164390
请参阅此处的评论：http: //api.jquery.com/unload/#dsq-comment-body-132164390
