angularjs - New to Typescript & Angular problems with Http Post -

i'm new angular , typescript , try create simple login page. i've created service in typescript invoked when user presses 'login' button. textboxes contains username , password bound correctly model, when send request backend written in c#, not hit breakpoint suspect because of format of message being sent on wire.

so using postman, i'm able invoke service , access_token when exporting request code in postman nodejs variant like:

var request = require("request");  var options = { method: 'post',   url: 'http://localhost:8081/login',   headers:     { 'postman-token': '34dd4d0f-ff16-db4f-ebae-dab945729410',      'cache-control': 'no-cache',      'content-type': 'application/x-www-form-urlencoded' },   form: { username: 'test', password: 'test', grant_type: 'password' } };  request(options, function (error, response, body) {   if (error) throw new error(error);    console.log(body); }); 

and typescript code

login(username: string, password:string) : observable<boolean> {          var headers = new headers();         headers.append('content-type', 'application/x-www-form-urlencoded')          var content = json.stringify({             username: username,              password: password,             grant_type: this.grant_type         });          return this.http.post(this.authenticationendpoint, content, {headers: headers})                 .map((response:response) =>  {                      let token = response.json() && response.json().token;                     if(token){                         //this.token = token;                         localstorage.setitem('user', json.stringify({username: username, token:token}));                         return true;                     }                      return false;                 });             } 

this results in error in visual studio code, says:

i'm not sure how should interpret error message, since method in webservice not invoked i'm pretty sure has http headers or format of http post.. ideas?

using urlsearchparams body of request , angular automatically set content type application/x-www-form-urlencoded

import { urlsearchparams } "@angular/http"      let body = new urlsearchparams();     body.set('username', username);     body.set('password', password);     .....   this.http.post(this.authenticationendpoint, body).map(..)