How does the Xero Invoice Number get populated?
The Invoices API endpoint has a InvoiceNumber element which is a unique alpha numeric code to identify an Invoice. You have 2 options when uploading Invoices to Xero:
- leave this blank and Xero will will auto-generate this from your Organisation Invoice Settings
- populate this with a value from a FileMaker field
In the fmAccounting Link (Xero Edition) file we are using the 2nd option to populate this with the value from the _kp_InvoiceID field (the primary key field for the Invoice in FileMaker). If you wish to change this to have Xero auto-generate the number for you simply disable/delete this line from the XeroInvoicePOSTCalc calculation formula:
We have a field in the Invoices table named XeroInvoiceNumber which we populate with the Xero Invoice Number value, regardless of the above settings.