How to initialise ReadOnlyDictionary?

Question

I have an unchanging dictionary that is exposed in a class.

Currently my code looks like

using System.Collections.Generic; using System.Collections.ObjectModel;  public class FooClass {     private static ReadOnlyDictionary<string, byte> _validRevisions          = new ReadOnlyDictionary<string, byte>(             new Dictionary<string, byte>() {                  { "1.0", 0x00 },                 { "1.1", 0x01 },                 { "1.2", 0x02 },                 { "1.3", 0x03 }             } );      public static ReadOnlyDictionary<string, byte> ValidRevisions => _validRevisions;      // other FooClass contents... } 

I've used the backing field _validRevisions as I could not figure out a better way of creating a shared constant dictionary property. Is there neater way to manage this or maybe I should just make the field public?

My main question being is there a shorter way to initialise the _validRevisions field itself? Creating a Dictionary inline to pass it into a Dictionary (that happens to be read only) seems a bit... of a code smell. Is it? Is there a better way?

EDIT: one more thing about the ROD I just noticed, there are no methods to support checking if it contains a given value... is there a reason for that related to it' read-only-ness?

Answer 1

If you don't mind having an IReadOnlyDictionary instead of a ReadOnlyDictionary, you could use this, since Dictionary implements IReadOnlyDictionary:

private static IReadOnlyDictionary<string, byte> _validRevisions     = new Dictionary<string, byte>        {            { "1.0", 0x00 },            { "1.1", 0x01 },            { "1.2", 0x02 },            { "1.3", 0x03 }         };  public static IReadOnlyDictionary<string, byte> ValidRevisions => _validRevisions;