Cannot find a differ supporting object '[object Object]' of type 'object'. NgFor only supports binding to Iterables such as Arrays
There you don't need to use this.requests= when you are making get call(then requests will have observable subscription). You will get a response in observable success so setting requests value in success make sense(which you are already doing).
this._http.getRequest().subscribe(res=>this.requests=res);
Remove this.requests from
ngOnInit(){ this.requests=this._http.getRequest().subscribe(res=>this.requests=res);}to
ngOnInit(){ this._http.getRequest().subscribe(res=>this.requests=res);}this._http.getRequest() returns a subscription, not the response value.The response value is assigned by the callback passed to subscribe(...)
You can declare the books (on line 2) as an array:
title: any = 'List of books are represted in the bookstore';books: any = []; constructor(private service: AppService){}ngOnInit(){ this.getBookDetails();}getBookDetails() { this.service.getBooks().subscribe(books => { this.books = books.json(); console.log(this.books); });}