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When should I use a struct instead of a class?


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:

  1. structs can have methods.
  2. structs cannot be inherited.

I understand the technical differences between structs and classes, I just don't have a good feel for when to use a struct.


Solution

  • 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.