C#

public class Storage
{
    int value;
}

public class Test
{
    public Test(Storage val)
    {
        m_val = val;
        m_val.value = 10;
    }
    private Storage m_val;
}

public class Test
{
    public Test(){}

    public int MyNumber
    {
        get{return m_i;}
        set{m_i = value;}
    }

    public int m_i;
}

public class SomeOtherClass
{
    public SomeOtherClass(){}


    public void ChangeValue(ref int i)
    {
        i = 5;
    }
}

    // Example
Test t = new Test();
SomeOtherClass soc = new SomeOtherClass();
t.MyNumber = 8;
soc.ChangeValue(ref t.m_i);
Console.Write(t.MyNumber);