return this._http.post(apiUrl, model)
            .map((res: Response) => {
                console.log(res.json());
                let user = Object(res.json());
                //let user = Object.keys(res.json());
                //console.log(user['Username']);

                if (user) {
                    localStorage.setItem('currentUser', JSON.stringify(user));
            }
        })

Object {Id: 101, UserName: "appatel", FirstName: "aarsh", LastName: "patel", Password: "aarsh"…}
Email: "aarshpatel@gmail.com"
FirstName: "aarsh"
Gender: "Male  "
Id: 101
LastName: "patel"
Password: "aarsh"
UserName: "appatel"