我建议使用 PayPal REST API https://developer.paypal.com/docs/api/ 因为他们付出了更多的努力.还有 SOAP API，但我不会使用它.好像过时了.

I'd suggest using PayPal REST API https://developer.paypal.com/docs/api/ as they putting more effort into it. There is also SOAP API, but I would not use it. It seems like dated.

您可以使用超现代的 Casablanca C++ REST SDK，这是来自 Microsoft 的开源框架，可从以下网址获得:https://github.com/Microsoft/cpprestsdk 来实现您的端点.

You can use ultra modern Casablanca C++ REST SDK which is an open source framework from Microsoft available at: https://github.com/Microsoft/cpprestsdk to implement your end-point.