Initializing an array in TypeScript using the subscribe function

Struggling to retrieve an array from my TypeScript function in Angular.

I've experimented with various methods, such as creating a public variable within the class to store courses and using 'return' before 'courses' in the function call, but I haven't had success. It should be a straightforward task, yet I can't seem to make it work.

getFallCourses(){

    let fallCourses : xCourse[];
    this.dataService.getFallCourses().subscribe((courses: xCourse[]) => {
            fallCourses = courses;
    });  
    return fallCourses;   

}

Answer №1

The observable is completing after the function returns, causing it to simply replace the local scoped fallCourses. If you prefer this behavior, consider returning an array that gets populated in the subscription. See below for an example:

getFallCourses(){
    let fallCourses: xCourse[] = [];

    this.dataService.getFallCourses().subscribe((courses: xCourse[]) => {
        fallCourses.push(...courses); // updates fallCourses directly
    });  

    return fallCourses;
}

However, a better approach would be to utilize the observable itself and subscribe to it from the caller.

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