Trouble with Angular2: Socket.io event not refreshing the view

I attempted to update my view upon receiving a socket event. This is what my component code looks like:

constructor(private _zone: NgZone){
    this.socket = io.connect('http://localhost:3000');
    this.socket.on('someEvent', function(data) {
        this._zone.run(() => {
            this.dataItem = data.item;
            console.log(this.dataItem);
        });
    });
}

After running the code, I encountered errors in the browser console:

EXCEPTION: TypeError: Cannot read property 'run' of undefined

By the way, the socket events are functioning properly in index.html.

Any assistance would be greatly appreciated.

Answer №1

Avoid the use of function () as it causes this to not point to the current class instance anymore. Opt for arrow functions instead:

this.socket.on('someEvent', (data) => {

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