无法从标头获取属性

Question

我在从http POST获取参数时遇到问题，当我使用标题时，我无法从对象中获取属性，但是当我对其进行评论并且不使用它时，我可以从req.body.type获取它们等等......

//Angular
let options = new RequestOptions({ headers:headers});

let postParams = {
  tipo: this.Tipoid,
  numid: this.numid,
  nombres: this.noms,
  apellidos: this.apellidos,
  edad:this.edad,
  genero:this.genero,
  cargo:this.cargo }
// let headers = this.getHeaders();
      console.log(postParams);

this.http.post("http://localhost:3000/api/empleados", postParams,options).
        map(res => res.json()).subscribe(data => {
  this.posts = data;
   console.log(this.posts);
  let alert = this.alertCtrl.create({
  title: 'Resultado',
  subTitle: this.posts.message,
  buttons: ['OK']
});
   alert.present();
});;
}

和Node.js代码

EmpleadosRoute.post(isAuth,(req, res) => {
// Create a new instance of the  model
var empleado = new Empleado();
console.log(req.body);

当我使用标题时，我得到这样的回复......

{ '{\n  "data": {\n    "tipo": "CC",\n    "numid": "343",\n    "nombres": "da",\n    "apellidos": "",\n    "edad": "",\n    "genero": "",\n    "cargo": ""\n  }\n}': '' }

但是当我评论标题时，我得到的回应如下：

{"data": "tipo": "CC",   "numid": "343",   "nombres": "da",   "apellidos": "",   "edad": "",   "genero": "",   "cargo": "": '' }