Why is an Add method required for { } initialization?
- by Dan Tao
To use initialization syntax like this:
var contacts = new ContactList
{
{ "Dan", "[email protected]" },
{ "Eric", "[email protected]" }
};
...my understanding is that my ContactList type would need to define an Add method that takes two string parameters:
public void Add(string name, string email);
What's a bit confusing to me about this is that the { } initializer syntax seems most useful when creating read-only or fixed-size collections. After all it is meant to mimic the initialization syntax for an array, right? (OK, so arrays are not read-only; but they are fixed size.) And naturally it can only be used when the collection's contents are known (at least the number of elements) at compile-time.
So it would almost seem that the main requirement for using this collection initializer syntax (having an Add method and therefore a mutable collection) is at odds with the typical case in which it would be most useful.
I'm sure I haven't put as much thought into this matter as the C# design team; it just seems that there could have been different rules for this syntax that would have meshed better with its typical usage scenarios.
Am I way off base here? Is the desire to use the { } syntax to initialize fixed-size collections not as common as I think? What other factors might have influenced the formulation of the requirements for this syntax that I'm simply not thinking of?
