NodeJs不发光，Socket.io

Question

Socket.emit（'delLoginSys'）主体似乎工作正常，它正在发送到html，但未被接收。 `

var io = require('socket.io')(serv, {});

io.sockets.on('connection', function(socket) {
    console.log("[DevLog] A Client has connected.");

    socket.on('Login', function(data) {
        var userVal = data.userVal;
        var passVal = data.passVal;
        if (userVal === "admin" && passVal === "password") {
            console.log("[DevLog] A Client has logged in.");
            socket.emit('delLoginSys');
        }
    });
});

这是html

<script>

    var socket = io();

    function LoginButton(data) {
        var userVal = document.getElementById("emailInput").value;
        var passVal = document.getElementById("passInput").value;

        socket.emit('Login', {userVal: userVal, passVal: passVal});
    }

    socket.on('delLoginSys', function() {
        document.getElementById("UserSec").parentElement.removeChild();
        console.log("del");
    });
</script>