Does the keyword 'this' return a reference or a value

Question

Whenever the keyword this is called inside a C# class, does it return a reference to the instance that it appears in, or does it return the value of the instance (like a copy)?

For example, would the following code print the number 23 (meaning this returned a copy of foo), or the number 96 (meaning this returned a reference to foo)?

class Program
{
    static void Main()
    {
        Foo foo = new Foo { 23 };
        foo.Bar();
        Console.Write(foo.FooBar);
    }
}

class Foo
{
    public int FooBar { get; set; }

    public void Bar()
    {
        Foo newFoo = this;
        newFoo.FooBar = 96;
    }
}

Answer 1

Since this relates to a reference type (class), it returns a reference to the instance. Using this is no different from using foo2 in the following code snippet:

var foo1 = new Foo();
var foo2 = foo1;

In the same way as foo2 only references (!) the object referenced by foo1, inside of the class, this only references the instance.

If it was different, it would be impossible to e.g. assign a value to a property of an object from inside a method, as using this would always result in a copied object, which in turn means you would never set the value of the original instance's field, which would be rather bad.

So, to cut a long story short: this holds a reference, not the value.

HTH 😊