Using: Windows Forms App (.NET Core)

So I’ve been programming in Windows Forms App (.NET Framework), and this code always worked. Since I was unable to find any other code specifically for .NET Core, I thought it was the same as the Framework version.

this.Hide();
CreateUserForm createUserForm = new CreateUserForm();
createuserform.ShowDialog();
this.Hide();

Visual studio says that the error is in the two “CreateUserForm”, and that it’s because I’m using them as a mode, but in that place I’m supposed to type names.

(CreateUserForm is the name of a form, just like a normal “Form2”.
Edit: I’m not sure if it has anything to do with the problem, but the text in the title bar of CreateUserForm, is “user creation”
Edit 2: Browsing on stack overflow I found this code
(new CreateUserFrorm()).Show();

but it shows the same error

i create a frame, then onClick make frame.content = myNewPage
In the button to open the new form?

If this code is verbatim, then it’s because createUserForm is not createuserform.

Otherwise, the problem could be in the constructor for CreateUserForm.
What does Visual Studio say the error is? Because that’s usually what’s wrong.

If the error was that, what should I type instead of createuserform?
C# devs
null reference exceptions

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