C# – Order of items in classes: Fields, Properties, Constructors, Methods

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Is there an official C# guideline for the order of items in terms of class structure?

Does it go:

  • Public Fields
  • Private Fields
  • Properties
  • Constructors
  • Methods
    ?

I'm curious if there is a hard and fast rule about the order of items? I'm kind of all over the place. I want to stick with a particular standard so I can do it everywhere.

The real problem is my more complex properties end up looking a lot like methods and they feel out of place at the top before the constructor.

Any tips/suggestions?

Best Answer

According to the StyleCop Rules Documentation the ordering is as follows.

Within a class, struct or interface: (SA1201 and SA1203)

  • Constant Fields
  • Fields
  • Constructors
  • Finalizers (Destructors)
  • Delegates
  • Events
  • Enums
  • Interfaces (interface implementations)
  • Properties
  • Indexers
  • Methods
  • Structs
  • Classes

Within each of these groups order by access: (SA1202)

  • public
  • internal
  • protected internal
  • protected
  • private

Within each of the access groups, order by static, then non-static: (SA1204)

  • static
  • non-static

Within each of the static/non-static groups of fields, order by readonly, then non-readonly : (SA1214 and SA1215)

  • readonly
  • non-readonly

An unrolled list is 130 lines long, so I won't unroll it here. The methods part unrolled is:

  • public static methods
  • public methods
  • internal static methods
  • internal methods
  • protected internal static methods
  • protected internal methods
  • protected static methods
  • protected methods
  • private static methods
  • private methods

The documentation notes that if the prescribed order isn't suitable - say, multiple interfaces are being implemented, and the interface methods and properties should be grouped together - then use a partial class to group the related methods and properties together.

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