In June 2020, a .NET Standard version of SharePoint CSOM was released. It means that now we can build projects for SharePoint, that target multiple platforms. At the beginning of 2021, a .NET Standard version of PnP-Sites-Core was also released (with a brand new name PnP.Framework and an updated codebase). However, there are some limitations in the .NET Standard version of SharePoint CSOM. Especially the lack of Remote Event Receivers (RER). The whole namespace was dropped. In some cases, you cannot replace RER with Webhooks without loss of functionality. Sometimes you just need RER or you're upgrading your code and cannot migrate RERs to webhook, since that's expensive.
So, let's bring support of Remote Event Receivers back to .NET Core \ .NET 5+.
The source code sample for this blog post is available at GitHub here (the master branch contains code for .NET Core, if you're looking .NET 5 sample, use net5 branch). More...