命名空间中不存在类型或命名空间名称（是否缺少程序集引用？）- 无法引用 class

Question

So, I'm doing some Angular + .NET Core course on Udemy and I stumbled upon a certain problem: I can't reference a class from ClientApp subfolder. I created an Angular + .NET Core project in Visual Studio 2019. My backend app is in route folder and the frontend app is in subfolder ClientApp of my backend app. Here are the screenshots of everything:

AuthController:

UserForRegisterDTO:

Solution Explorer:

What am I getting wrong here?

EDIT: Out of some reason, I can see every folder in my namespace when I start typing but ClientApp. Here's the screenshot:

Answer 1

If you check your IDE, it clearly shows that it cannot find DatingApp.SPA.ClientApp namespace.

Open your UserForRegisterDTO.cs file and check which namespace it is in. Then add that namespace instead of the one causing the issue.

If you are using Visual Studio (and it looks like you are), go with the cursor to the place in the method where UserForRegisterDTO type is underlined and press Ctrl +. . It suggest ways of fixing this error, most probably automatically telling you which namespace is missing.

If neither works, please update your question with more details.