javascript 如果服务器出现故障，如何捕获浏览器抛出的 ERR_CONNECTION_REFUSED？
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How to catch ERR_CONNECTION_REFUSED thrown by browser if server goes down?
提问by Matt Vukas
I think this question is pretty straightforward, but I haven't found an answer yet in the official Socket.io docs.
我认为这个问题很简单，但我还没有在官方的Socket.io docs 中找到答案。
I have my Socket.io server and client communicating successfully, and when I shut down the server, the client will attempt to reconnect with the server unsuccessfully. This is shown in the Chrome developer's console here:
我的 Socket.io 服务器和客户端通信成功，当我关闭服务器时，客户端将尝试重新连接服务器失败。这显示在 Chrome 开发人员的控制台中：
Is there any way to detect this event in the client-side Javscript and react to it some way? I'm thinking I would display a dialog on the page, such as "Sorry, server is under heavy load", etc.
有没有办法在客户端 Javscript 中检测到这个事件并以某种方式对其做出反应？我想我会在页面上显示一个对话框，例如“抱歉，服务器负载过重”等。
回答by Matt Vukas
The correct way to handle this, as of Socket 1.x, is to use the Managerobject for a given socket. It throws a connect_errorevent that can be handled as shown:
从 Socket 1.x 开始，处理此问题的正确方法是使用给定套接字的Manager对象。它抛出一个connect_error事件，可以按如下所示进行处理：
socket.io.on('connect_error', function(err) {
// handle server error here
console.log('Error connecting to server');
});
回答by glortho
This should work:
这应该有效：
var socket = io('http://localhost');
socket.on('connect_error', function(err) {
// notify user
});
回答by Glenn Carver
As of now and in the past there is no way to "handle" the redmessages. You can't hide them.
截至目前和过去，没有办法“处理”红色消息。你无法隐藏它们。
Reference: https://stackoverflow.com/a/43056626/5563074
参考：https: //stackoverflow.com/a/43056626/5563074
You can't hidethem but socket.io does have a way to catchthem like presented earlier.
您无法隐藏它们，但 socket.io确实有一种方法可以像前面介绍的那样捕获它们。
socket.on('connect_error', function(e){
//Do something
//console.log(e);
});
Docs: https://socket.io/docs/client-api/#Event-%E2%80%98connect-error%E2%80%99
文档：https: //socket.io/docs/client-api/#Event-%E2%80%98connect-error%E2%80%99
