using System;

​

public class SomeThing

{

    public string SomeValue { get; set; }

}

​

public class Program

{

    public static void Main()

{

    var oldValueThing = new SomeThing()

    {

        SomeValue = "Old Value"

    };

    MyMethod(oldValueThing, MyRefMethod(ref oldValueThing));

}

​

public static SomeThing MyRefMethod(ref SomeThing str)

{

​

    str.SomeValue = "new Value";

    return null;

}

​

public static void MyMethod (SomeThing originalThing, SomeThing doesntMatterThing)

{

    Console.WriteLine(originalThing.SomeValue);

}

}