add header in angular

1import {Injectable} from '@angular/core';
2import {Http, Headers} from '@angular/http';
3
4@Injectable()
5export class HttpClient {
6
7  constructor(private http: Http) {}
8
9  createAuthorizationHeader(headers: Headers) {
10    headers.append('Authorization', 'Basic ' +
11      btoa('username:password')); 
12  }
13
14  get(url) {
15    let headers = new Headers();
16    this.createAuthorizationHeader(headers);
17    return this.http.get(url, {
18      headers: headers
19    });
20  }
21
22  post(url, data) {
23    let headers = new Headers();
24    this.createAuthorizationHeader(headers);
25    return this.http.post(url, data, {
26      headers: headers
27    });
28  }
29}
30