why should we use subscribe() over map() in Angular?

Question

I am trying to take advantage of observables in angular2 and got confused on why should i use map() over subscribe(). Suppose i am getting values f

Answer 1

Think map as a middleware which transforms the response.

this.http.get('http://172.17.40.41:8089/api/Master/GetAllCountry')
.map(r=>r.json())
 .subscribe(result => {
              // here result would have json object that was parsed by map handler...
            },failurCallback,completeCallback)

subscribe is used to invoke the observable, please read a good doc on cold-vs-hot-observables