Revisiting the Alphabet Range with the latest .NET

Jan 19 2008

While Richard Bushnell was showing off how old problems can be implemented very concise with LINQ he also made use of an extension method to the int Type.

It has been quite some time since I did an update to the .NET goodies. In there there was an implementation to be able to iterate over the letters of the alphabet.

Extension methods and LINQ allow the provision of a concise implementation that can be easily used to obtain character ranges over the alphabet.

static class CharStuff
{
    static char[] content =
        new char[] {
            'a','b','c','d','e','f','g',
            'h','i','j','k','l','m',
            'n','o','p','q','r','s',
            't','u','v','w','x','y','z'
        };

    public static char[] To(this char start, char end)
    {
        char[] space = content;
        char[] boundaries = new char[] { start, end };
        if (start > end)
        {
            space = content.Reverse().ToArray();
            // start, end = end, start; GRR, why not like in Ruby?
            boundaries = boundaries.Reverse().ToArray();
        }

        var result = from c in space
                        where c >= boundaries[0] && c <= boundaries[1]
                        select c;
        return result.ToArray();
    }
}

Most code deals with the ability to get an array with alphabet elements ordered backwards. I.e. you can use this extension like that:

Array.ForEach('f'.To('l'), Console.WriteLine);
Array.ForEach('l'.To('a'), Console.WriteLine);

Far from being feature complete, all those examples just show that Microsoft is doing something right: We are writing less lines of code that are more readable in order to get things done.