I know this is not a new question; however, if you search online, you will mostly find articles discussing the older .NET Framework. Here is my way of dealing with 400 (BadRequest) and 404 (NotFound) errors using the latest .NET Core 3.0 WebAPI methods.

Postman requires no introductions and plenty of resources about this tool can be found online. However, while testing I recently noticed, that the binding of JSON objects to C# primitive types or POCO classes is not documented in detail.

We are going to see different scenarios of binding while we test against a .NET WebAPI and try to answer the question “why my action is not getting called when everything is set up in Postman?”.