MSDN says that you should use structs when you need lightweight objects. Are there any other scenarios when a struct is preferable over a class?
Some people might have forgotten that:
I understand the technical differences between structs and classes, I just don't have a good feel for when to use a struct.
MS Learn has the answer: Choosing Between Classes and Structures.
Basically, that page gives you a 4-item checklist and says to use a class unless your type meets all of the criteria.
Do not define a structure unless the type has all of the following characteristics:
- It logically represents a single value, similar to primitive types (integer, double, and so on).
- It has an instance size smaller than 16 bytes.
- It is immutable.
- It will not have to be boxed frequently.
As @Simon said, structs provide "value-type" semantics so if you need similar behavior to a built-in data type, use a struct. Since structs are passed by copy you want to make sure they are small in size, about 16 bytes.