Can I detect whether I've been given a new object as a parameter?

Question

Short Version

For those who don\'t have the time to read my reasoning for this question below:

Is there any way to enforce a policy of "new obje

Answer 1

As a possible partial solution if you only wanted one of an object to be consumed by a method maybe you could look at a Singleton. In this way the method in question could not create another instance if it existed already.

Answer 2

No, basically.

There's really no difference between:

var x = new ...;
Foo(x);

and

Foo(new ...);

and indeed sometimes you might convert between the two for debugging purposes.

Note that in the DataRow/DataTable example, there's an alternative approach though - that DataRow can know its parent as part of its state. That's not the same thing as being "new" or not - you could have a "detach" operation for example. Defining conditions in terms of the genuine hard-and-fast state of the object makes a lot more sense than woolly terms such as "new".

Answer 3

No. And if there is some reason that you need to do this, your code has improper architecture.