C#. How to save information between Windows Forms?

Question

C++ / C#

Good afternoon.
I have a main menu which has an "advanced" button. When this button is pressed, another window appears, and the Enabled parameter of the main window becomes false.
Question: how to set the Enabled main window to true when clicking on "Cancel" and close the additional one ?

Answer 1

There are a lot of options:
1. Pass a link to an instance of the class of the main window of the form, through the constructor when creating another window.
2. Pass a delegate to the function, also through the constructor
3. Create an event in the dependent window class and subscribe to it after creation.
etc.

Answer 2

https://docs.microsoft.com/en-us/dotnet/api/system...
Open a new form through a dialog. After closing, you will have the result.
In addition, use the Global object with states, and in forms, only change its properties.