callback - 套接字io发出失败的回调

Question

有没有办法知道套接字io发出失败和成功，就像ajax回调方法一样:onSuccess，onError？
对于io套接字，我只能找到:

socket.emit('publish', {message:'test message'},function (data) { alert("")})

仅当服务器发送ack响应时才调用此回调。但这不适用于这种情况:

At the moment of emit message to server, there is bad network or lost connection, that means server not receive this message, so the client callback function is not called.

我想要的是:

When I call the socket io emit, if it fails, I want to retry 3 times.

Answer 1

我知道这是一篇过时的文章，但是以防万一有人仍然遇到麻烦。

var socket = new io.connect('http://localhost:3000', {
    'reconnection': true,
    'reconnectionDelay': 1000,
    'reconnectionDelayMax' : 5000,
    'reconnectionAttempts': 3
});
socket.on('connect_error', function() {
    console.log('Connection failed');
});
socket.on('reconnect_failed', function() {
    // fired only after the 3 attemps in this example fail
    console.log('Reconnection failed');
});

更多信息在这里-> https://socket.io/docs/client-api/#manager-reconnectionAttempts-value