Initializing default values for private fields in constructors explicitely.. WTF?

Question

Consider the following code snippet from .NET 4.0 library:

private T[] array; 
private static T[] emptyArray; 
private int size; 
private int version; 

static Stack() 
{ 
    Stack<T>.emptyArray = new T[0]; 
} 

public Stack() 
{ 
    array = Stack<T>.emptyArray; 
    size = 0; 
    version = 0; 
}

Is there any reason behind initializing value type private fields to default values (size and version in the example above) explicitely other than coding standards of the company?

Answer 1

I think it's usually a good practice to initialize collections, primarily because it ensures the developer that he does not need to initialize anything on usage, and just assumes the variable has been initialized.

public class Store
{
    public Store()
    {
        // Ready to go!
        Products = new List<Product>();
    }

    public string Id {get;set;}
    public IList<Product> Products {get;set;}
}

You jump through the hoopla of having to check if the collection has been initialized, if not do so, else... yawn

Answer 2

IMO, there is no need or benefit to initialize private variables to their default values (unless it's part of standards).

Edit: few times, it may make sense (as it improves code readability) - for example

public const OP_GET = 0;
public const OP_ADD = 1;
...

private int operation = OP_GET;

Answer 3

If they are primitive data type you don't need to initialize they will always take their default value

int,long etc. will always have its default value as 0 while bool will have false etc.

if it is a reference type you may have to initialize so that they have some default value (according to your logic) and avoid Null Reference errors

Answer 4

No, there is not, at least not a technical reason. Perhaps in some cases one might do that to make a point, for example if you have a counter variable of some sort and you want to make clear it starts from zero. But I think even this is a bit questionable.