为什么我用2个不同的“实例”获得相同的值

Question

我知道javascript“类”与大多数语言完全不同，但是我想弄清楚为什么当我在构造函数中设置2个不同的值时，来自SignalR的回调为两个实例打印出20个。

class gameLoad{
            constructor(value) {
                this.value = value;
            }

            init(){
                // create the network object and hook it's functions update
                this.network = $.connection.testHub;
                this.network.client.hello = this.sayHello.bind(this);

                console.log(this.value);
            }

            // this is called from signalR and 'this' now refers to the signalR hub inside this function. how can I get the class instance?
            sayHello(){
                console.log(this.value);        //<--- this prints 20 2 times
            }

            create(){
                var self = this;

                // start the hub connection
                $.connection.hub.start().done(function () {
                    console.log("Started!")
                    console.log("Calling server function.");

                    // make our first network call which will turn around and fire client.hello which is bound to this classes sayHello()
                    self.network.server.hello();
                });
            }
        }

        var game1 = new gameLoad(10);

        game1.init();
        game1.create();

        var game2 = new gameLoad(20);

        game2.init();
        game2.create();