javascript - 如何清除从 Controller 分配的事件？

Question

何时、何处和如何当 Controller 不再相关时，我应该摆脱旧的事件监听器？

考虑 SPA有两条路线:/login 和 /loggedin

app.factory('socket', ['$window', function(window) {
    return window.io();
}]);
app.controller('loginController', ['socket', function (socket) {
    this.tryLogin = function(credentials) {
        socket.emit('login', credentials);
    }
    sokcet.on('loginResponse', function(data) {
        if (data.status == 'OK') {
            // Navigate to loggedInController
        } else {
            // Show error message and keep listening - user might try again
        }
    });
}]);
app.controller('loggedInController', ['socket', function (socket) {/* Logged in, but loginController is still listening for loginResponse */}]);

问题:

• 当导航到 /loggedin 时，loginResponse 事件保持监听
• 当导航回 /login 页面时，添加了 new 监听器(实际上我现在有 2 个监听器)

Answer 1

看看 Angular 的 $scope.$on('$destroy')事件并将其与 socket.io 的 removeListener 一起使用方法。像这样:

app.controller('loginController', ['$scope', 'socket', function ($scope, socket) {
    this.tryLogin = function(credentials) {
        socket.emit('login', credentials);
    }

    socket.on('loginResponse', loginResponse);

    $scope.$on('$destroy', function() {
        socket.removeListener('loginResponse', loginResponse);
    });

    function loginResponse(data) {
        if (data.status == 'OK') {
            // Navigate to loggedInController
        } else {
            // Show error message and keep listening - user might try again
        }
    }
}]);