angular - Download file using Typescript. response.json() --> Unexpected token P in JSON

Question

I have an internet method to download a 'contract' file. Required Parameters are: Method get. Parameters need to send in header. Like in postman.

When I send those, web service get me contract.

I tried this code service, that show me an error like below. Please follow my code.

 public contract_download(id: string): Observable<Sale[]> {
    let headers = new Headers();
    headers.append('x-access-token', this.auth.getCurrentUser().token);
    headers.append('_id', id);
    return this.http.get(Api.getUrl(Api.URLS.contract_download), {
      headers: headers
    })
      .map((response: Response) => {
        let res = response.json();
        console.log(res)
        if (res.StatusCode === 0) {
          this.auth.logout();
        } else {
          return res.StatusDescription.map(sale => {
            return new Sale(sale);
          });
        }
      });
  }

This code show:

core.js:1440 ERROR SyntaxError: Unexpected token P in JSON at position 0 at JSON.parse () at Response.Body.json (http.js:1091) at MapSubscriber.eval [as project] (sales.service.ts:111) at MapSubscriber._next (map.js:79) at MapSubscriber.Subscriber.next (Subscriber.js:92) at XMLHttpRequest.onLoad (http.js:1591) at ZoneDelegate.invokeTask (zone.js:421) at Object.onInvokeTask (core.js:4724) at ZoneDelegate.invokeTask (zone.js:420) at Zone.runTask (zone.js:188)

I used this function

   contract_download(id: string) {
   this.ws.contract_download(id).subscribe(
   saledownload => {
    console.log(saledownload)
   }
 }

My question is: How to send those parameters and download my contract? What is my problem in this code, and how to change it?

Please any idea for my post?

Answer 1

Waitting for answers