does anyone know the state of the Paypal .NET SDK? I just wonder, according to https://github.com/paypal/PayPal-NET-SDK/releases, the latest version is a V2.0 Release Candidate, but it is already 2 years old, and it seems like there was never an actual V2.0 release. Has this project died? Should I rather use the Paypal REST API directly?
Don't use any version of the v1 PayPal-NET-SDK (neither 1.x nor 2.0 rc2)
Old answer:
Use the new v2 Checkout-NET-SDK
If it does not (yet) support the API you want to integrate (e.g. the new Subscriptions API would be one example), then use direct HTTPS calls for that REST API
2024 update:
As of this writing Checkout-NET-SDK is also deprecated and not supported. For all new integrations PayPal says to use direct HTTPS integrations of first getting an access token (which can be cached for up to 9 hours) and use that access token for w/e operation, with requests and responses in JSON format.
For the payer approval flow don't redirect away from your website to a PayPal URL; use the JS SDK for payer approval: https://developer.paypal.com/docs/checkout/standard/integrate/
(The backend samples at that location are given in node.js , but the same can be implemented in any language/environment including .NET of course)