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Delphi ActiveX Requires Chilkat v11.0.0+

PayPal: Get the next invoice number

See more PayPal Examples

Read invoice_number for use as the customer-facing number on a draft. It is distinct from the PayPal invoice ID used in API paths. If you do not need to choose a number, omit it when creating the invoice.

PayPal documentation

Chilkat Delphi ActiveX Downloads

Delphi ActiveX
var
success: Integer;
http: TChilkatHttp;
resp: TChilkatHttpResponse;
body: TChilkatJsonObject;
errorInfo: TChilkatJsonObject;
result: TChilkatJsonObject;
parsed: Integer;

begin
success := 0;

//  See Unlock Chilkat before making requests.
//  For the merchant's internal backoffice application. Load the sandbox token
//  from the merchant's credential store. Keep it out of publicly distributed apps.
//  See Get a PayPal access token.
http := TChilkatHttp.Create(Self);
http.AuthToken := 'SANDBOX_ACCESS_TOKEN';
resp := TChilkatHttpResponse.Create(Self);

//  The customer sees the invoice number. Subsequent REST calls need the invoice ID
//  instead.

body := TChilkatJsonObject.Create(Self);

success := http.HttpJson('POST','https://api-m.sandbox.paypal.com/v2/invoicing/generate-next-invoice-number',body.ControlInterface,'application/json',resp.ControlInterface);
if (success <> 1) then
  begin
    Memo1.Lines.Add('No HTTP response: ' + http.LastErrorText);
    Exit;
  end;
if ((resp.StatusCode < 200) or (resp.StatusCode >= 300)) then
  begin
    errorInfo := TChilkatJsonObject.Create(Self);
    errorInfo.Load(resp.BodyStr);
    Memo1.Lines.Add('HTTP ' + IntToStr(resp.StatusCode) + ' ' + errorInfo.StringOf('name') + ' ' + errorInfo.StringOf('details[0].issue'));
    Memo1.Lines.Add('PayPal debug ID: ' + errorInfo.StringOf('debug_id'));
    Exit;
  end;

result := TChilkatJsonObject.Create(Self);
parsed := result.Load(resp.BodyStr);
if (parsed <> 1) then
  begin
    Memo1.Lines.Add('Expected a JSON response; HTTP ' + IntToStr(resp.StatusCode));
    Exit;
  end;
Memo1.Lines.Add('Next number: ' + result.StringOf('invoice_number'));