Problem with delegates in C#

Question

In the following program, DummyMethod always print 5. But if we use the commented code instead, we get different values (i.e. 1, 2, 3, 4). Can anybody please explain why this is

Answer 1

If you look at the code generated (using Reflector) you can see the difference:

private static void Method2()
{
    List list = new List();
    Methodx item = null;
    <>c__DisplayClassa classa = new <>c__DisplayClassa();
    classa.i = 0;
    while (classa.i < 5)
    {
        if (item == null)
        {
            item = new Methodx(classa.b__8);
        }
        list.Add(item);
        classa.i++;
    }
    foreach (Methodx methodx2 in list)
    {
        Console.WriteLine("In main method c = " + methodx2(null));
    }
}

When you use the initial code it creates a temporary class in the background, this class holds a reference to the "i" variable, so as per Jon's answer, you only see the final value of this.

private sealed class <>c__DisplayClassa
{
    // Fields
    public int i;

    // Methods
    public <>c__DisplayClassa();
    public int b__8(object obj);
}

I really recommend looking at the code in Reflector to see what's going on, its how I made sense of captured variables. Make sure you set the Optimization of the code to ".NET 1.0" in the Option menu, otherwise it'll hide all the behind scenes stuff.