The dynamic fusion of Typescript and Angular 2 creates a powerful

private nodes = [];

constructor(private nodeService: NodeService) {}    

    this.nodeService.fetchNodes('APIEndpoint')
            .subscribe((data) => {
            this.nodes.push(data);
        });


        console.log(this.nodes)

This is the component responsible for fetching and storing data.

fetchNodes(url) {
    return this.http.get(url)
    .map((res) => res.json())
}

This is my service where I retrieve and structure the data.

However, when I check the contents of `this.nodes` in my component using console.log, the output displays as follows:

[1: Array[0]]

You can view the structure of the data here.

My issue arises when trying to access the first element of `this.nodes` by console.logging `this.nodes[0]`. The result returned is 'undefined'. What could be causing this problem?

Answer №1

As mentioned by Juan, it's crucial to reposition the console.log inside the callback function.

constructor(private dataHandlingService: DataHandlingService) {}    

    this.dataHandlingService.fetchData('APIRoute')
            .subscribe((response) => {
            this.data.push(response);
            console.log(this.data)
        });

However, it appears that your code suggests a lack of understanding regarding the asynchronous behavior of the service being used. I recommend thoroughly reading and comprehending the linked answer for further insight.

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