array of interface?

[haroldsphsu]

Hi,

I understand that I cannot create an instance of an interface, but why
is it ok to do the following? What is it creating?

foo = New System.ComponentModel.IEditableObject(10) {}

whereas the following will get a compiler error ('New' cannot be used
on interface):

foo = New System.ComponentModel.IEditableObject(10)

Thanks,
Harold

 

[Mattias Sjögren]

What is it creating?

An 11-element array of the interface type, just like your subject
says.


Mattias

 

[haroldsphsu]

But why is it an error if I don't specify the empty array element
initializer?

 

[Herfried K. Wagner [MVP]]

I understand that I cannot create an instance of an interface, but why
is it ok to do the following? What is it creating?

foo = New System.ComponentModel.IEditableObject(10) {}

An array with items of type 'IEditableObject' containing 11 elements with
indices 0 through 10.

whereas the following will get a compiler error ('New' cannot be used
on interface):

foo = New System.ComponentModel.IEditableObject(10)

In this case the curly braces are required to make the compiler aware that
an array should be created instead of calling a non-existing constructor.

 

[haroldsphsu]

Sorry, I think I got it. Without the array initializer, it's not
actually an array I'm creating.

 

[haroldsphsu]

Thanks Herfried and Mattias!