Sunday, October 31, 2010

Random Enum in C#

I wrote this because.. well.. I can. 8D

If you use this code, please give Protiguous some credit. (Too bad adSense doesn't allow one to ask for clicks. Because that'd be cooler!)

Explanation:
  1. Initialize a newly seeded rng with an overkill of LINQ.
  2. Initialize a thread safe access control.
  3. Generate a list of names for each defined enum.
  4. ... and return one of those enums.


Here is some untested sample code:
enum ourEnums { One, Two, Three, Four, Five };

//I know we could use a for loop, but I love foreach so much more..
foreach ( var i in Enumerable.Range( 0, 10 ) ) {
   Console.WriteLine( RandEnum() );
 }

Note: If there are any uppercase/lowercase/typos... let's just blame it on blogspot/browser/politics/etc... as always: It Works On My Machine.

And here is my sample code for returning a random enum in C#:
namespace Examples {
    using System;
    using System.Linq;
    using System.Threading;

    public class Example {

        private static readonly Random oti = new Random( Guid.NewGuid().ToByteArray().Sum( b => b * b.GetHashCode() ) );

        private static readonly ReaderWriterLockSlim otia = new ReaderWriterLockSlim( LockRecursionPolicy.SupportsRecursion );

        public static T RandEnum() {
            if ( !typeof( T ).IsEnum ) { return default( T ); }

            var names = Enum.GetNames( typeof( T ) );
            try { otia.EnterWriteLock(); return ( T )Enum.Parse( typeof( T ), names[ oti.Next( 0, names.Length ) ] ); }
            finally { otia.ExitWriteLock(); }
        }

    }
}

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