C# how to create an instance of a class in one function and then use that same instance in another function

Question

This is probably a really short answer but I just don't know the syntax for it and cant find examples of it anywhere online that involve multiple instances of classes that depend on each other.

I have this but its not working because the instance of game cannot be found because it is in another function.

All of the resources I can find are on referencing strings and objects outside/between methods but this don't even know what to do because I have tried all of those ways that they said to do with objects and variables but I just cant get it going. Because when i do it those ways as shown buy creating it before hand it always clears game to null just before it enters the second function.

public void Go()
    {
        MockFiler Mock = new MockFiler("###\n# #\n#@#\n###");
        Game game = new Game(Mock);
        game.Load("h:\theFileNameDoesNotMatterAsItReturnsAString"); // All gets created fine and used fine

        string Level = game.Level;
        View.ShowGame(Level);  // Some winforms code in here
    }


    // As soon as trigger is setoff in the winforms code it calls this function
    // as soon as the attention point comes back in this class to here the game is == null
    public void PassMove(Direction Direction) 
    {
        game.Move(Direction);  // so the instance of game becomes null and i cant call this function inside it
        string Level = game.Level;
        View.ShowGame(Level);
    }

I have tried all of those things like calling Game outside of the first method and then setting it inside that first method but it always clears it. I think it is to do with the MockFiler not setting it properly or note being accessible or something little and silly.

Answer 1

You should create the instance globally for both Game and MockFiler , It will be outside of both functions,

 //Creating instance and passing 
 MockFiler Mock = new MockFiler("###\n# #\n#@#\n###"); 
 //Creating instance  for Game
 Game game = new Game(Mock);
 //Now these can be accessed anywhere within the methods 
 public void Go()
  {         
    game.Load("h:\theFileNameDoesNotMatterAsItReturnsAString");
    string Level = game.Level;
    View.ShowGame(Level); 
}    
public void PassMove(Direction Direction) 
{
    game.Move(Direction);  
    string Level = game.Level;
    View.ShowGame(Level);
}