Stack and Heap memory allocation in .net

I've been reading different articles/pages on this topic and finally came to this article, which led me to a confusion!

In the article, it's mentioned that Value Types always go where they were declared , by which the author meant, value types may reside in either the stack or the heap, as per how/where they're declared.

Let me put down a code snippet to make myself more clear:

public class Test
{
    int testInt;
    string testString;
}

int anInt;
string aString;
Test testObj;
testObj = new Test();

After executing these lines of code, the memory allocation will look something like this:

The struct testInt is stored in the heap, since it was declared in the Test class.

Keeping this example in mind, let us see a simple Form.cs code behind where I'm declaring an integer.

using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        public int anotherInt;
    }
}

My confusion part:

In this case, where is anotherInt allocated to? Stack or Heap? By the looks of it, I think most of the answers will be "Stack". But, isn't this variable declared in a class called Form1 ? So, as per the first code snippet above, shouldn't it be going to the heap? If yes, then under what all circumstances would a struct be allocated to a Stack? Only if it is declared inside a method? But still, won't a method come under a class, which again should be stored in a heap?

A lot of questions I know! But just curious to know what's happening. I hope my question is clear.

---

In your example anotherInt would be allocated to the Heap. This is because anotherInt is a field of Form1 , which is a Heap allocated object. The Stack is associated with a thread & contains only the references/objects necessary for the currently executing code. So to answer your question about methods coming under a class, you're not entierly correct there.

While methods belong to a class, they are executable blocks of code rather than memory blocks associated directly with a class(which is what anotherInt is). One of the best ways to examine this type of allocation is to use a memory debugger like WinDbg & actually examine your thread stacks vs. the Heap. This will give you the clearest picture of where a particular struct is actually allocated.

In an extremely simplified sense: Stack = addresses necessary for currently executing code stack, Heap = everything else. But ultimatley Jon B is spot on w/ his link to Eric's blog. You really don't need to know where your objects are allocated.

EDIT: Including the blog link.

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In your example anotherInt will be located on the heap along with the rest of the instance of Form1 (assuming you create one of course).

To create a local int, the variable must be declared in a method or a property. Eg

void Foo()
{
    int localInt = 42;
}

Now, just because a value type is declared in a method doesn't necessarily mean that it goes on the stack. Eg captured variables are handled differently.

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