How to save a ref variable for later use?

c# reference ref
Joey Williams picture Joey Williams · Aug 31, 2011 · Viewed 8.9k times · Source

So this works..

public MyClass(ref Apple apple)
{
    apple = new Apple("Macintosh"); // Works fine
}

But is it possible to do something like this?

private Apple myApple;

public MyClass(ref Apple apple)
{
    myApple = apple;
}

public void ModifyApple()
{
    myApple = new Apple("Macintosh"); // does not change the input variable like the first example did
}

When the ref variable is copied to the member variable myApple it appears to lose it's 'ref-ness' and re-assigning it no longer changes the input variable. Is there a way around this?

Answer

Joey picture Joey · Aug 31, 2011

ref-ness is a property of parameters of functions and arguments you are passing to functions. It's not a property of variables (or even fields) in general.

So indeed, what you are trying there is doomed from the start.

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