var cors = new EnableCorsAttribute(origins:"*",methods: "*", headers: "*");
        config.EnableCors(cors);

[Route("SaveorUpdateCategory")]
    [HttpPost]
    public IHttpActionResult SaveorUpdateCategory(ModelCategory model)
    {
        string res = objcate.SaveorUpdateCategory(model);
        return Ok(res);

    }

SaveorUpdateCategory( model: any): Observable<any> {
     this.headers= new Headers({ 'Content-Type': 'application/json' })
    this.options = new RequestOptions({ headers: this.headers });
   let body = JSON.stringify(model);
   return this._http.post(this.BaseURL+"Category/SaveorUpdateCategory", model, this.options)
       .map((response: Response) => <any>response.json())
        .catch(this.handleError);