how to pass api key along with the post request

Question

I'm using angular and have post request, I got unauthorize error which turned out. I need to pass the api key as well, here is my post request:

SendToBackEnd(){         
    var x=new mymodel();
    x.settlementCurrency='EUR';
    x.customerReference='m455';
    x.paymentReference='65465465';
    this.http.post("address",x).subscribe(s=>{
    });
}

Could you please help me with that? no idea how I should pass the api key along with my request

Answer 1

Where is located address provide parameter for Auth to your end point

var address = 'https://adressToEndpoint.com/?apiKey=key 

  SendToBackEnd(){         
        var x=new mymodel();
        x.settlementCurrency='EUR';
        x.customerReference='m455';
        x.paymentReference='65465465';
        this.http.post("address",x).subscribe(s=>{
        });
      }