Dynamic arrays

[Roger Webb]

I'm sure this has been asked before ... however, I didnt find it ..so I'm
asking it anyway.

I've got a function that has to return an int[]. The function has to build
it, however, I dont know the number of items in order to create it. Whats
the easiest/fastest way to create one of an unknown size?

- Roger

 

[Daniel O'Connell [C# MVP]]

I'm sure this has been asked before ... however, I didnt find it ..so I'm
asking it anyway.

I've got a function that has to return an int[]. The function has to
build
it, however, I dont know the number of items in order to create it.
Whats
the easiest/fastest way to create one of an unknown size?

Either determine the size before hand(if thats possible without being to
computationally expensive) or use ArrayList\List<T>(if you are using the 2.0
framework), add items to it, and call ToArray() to create an array out of
the members.

 

[Bruce Wood]

When you say that you "don't know the number of items", I assume that
you mean at compile time, when you're writing the program. The easiest
way to do this at run time is using an ArrayList:

ArrayList list;

.... list.Add(myInt); ... (fill up the ArrayList)
return (int[])list.ToArray(typeof(int));