1. Search the library on Alipay's homepage, click on the library service to borrow books, select provinces and cities, and click on the QR code card to see your reader ID number.
2. Log in to official website of the National Library, enter the personal information of the reader card information of the borrowing service in the reader service, and the card number will be automatically queried and displayed.
3. Ask the staff of the information desk of the National Library to provide personal information, and you can query the system to retrieve the card number.
The above is the way for Huadu Library to retrieve readers' ID numbers. I hope it will help you.