Question

I would like to be able to assign values to list objects without directly referencing them:

Pseudo example:

List<int> intList = new List<int> { 0 };
???? intPointer = ref intlist[0];

*intPointer = 1;  // I know * isn't possible here, but it is what I'd like to do

Console.WriteLine(intList[0]);

and it would output 1.

I’m thinking that this isn’t possible, but I just wanted to make sure I wasn’t missing anything.

Also, I’m not looking for an example that uses unsafe, I’m curious if this is possible in managed code.

Answer 1

C# doesn’t have a concept of “ref locals” (the CLR does though). So you’ll need to wrap the values in a reference type that you can mutate. For example,

public class Ref<T> where T : struct
{
    public T Value {get; set;}
}

List<Ref<int>> intRefList = new List<Ref<int>>();
var myIntRef = new Ref<int> { Value = 1 };
intRefList.Add(myIntRef);

Console.WriteLine(myIntRef.Value);//1

Console.WriteLine(intRefList[0].Value);//1

myIntRef.Value = 2;

Console.WriteLine(intRefList[0].Value);//2

Edit: C# 7.0 added ref locals but they still can’t be used in this way because you can’t put ref locals into an array or list.