Question

In a recent project I was working I created a structure in my class to solve a problem I was having, as a colleague was looking over my shoulder he looked derisively at the structure and said ‘move it into a class’.

I didn’t have any argument for not moving it into a class other than I only need it in this class but this kind of falls down because couldn’t I make it a nested class?

When is it ok to use a structure?

Answer 1

You should check out the value type usage guidelines: http://msdn.microsoft.com/en-us/library/y23b5415(vs.71).aspx

The article lists several important points but the few that I feel are the most valuable are the following

• Is the value immutable?
• Do you want the type to have value semantics?

If the answer to both questions is yes then you almost certainly want to use a Structure. Otherwise I would advise going with a class.

There are issues with using structures with a large amount of members. But I find that if I consider the two points above, rarely do I have more than the recommended number of members / size in my value types.