library to determine indefinite article of a noun

Question

Are there any libraries for .NET that deal with determining the Indefinite Article of a noun?

My crude attempt is below, which will probably work for 99% of my usage (which is acceptable) just wondering if there are any established alternatives?

public static string GetIndefinateArticle(string noun)
{
    if(string.IsNullOrEmpty(noun))
        return noun;

    var first = noun[0];

    if(first == 'a' ||
        first == 'e' ||
        first == 'i' ||
        first == 'o')
        return "an " + noun;

    return "a " + noun;
}

Answer 1

What i would do is:

var first = noun[0];
var second = noun[1];

if(first == 'a' ||
    first == 'e' ||
    first == 'i' ||
    first == 'o')
    return "an " + self;

if(first == 'u')
    if (second == 'n' ||
        second == 'l')
        return "an " + self;

if(first == 'h')
    if (second == 'i')
        return "an " + self;

return "a " + self;

So you can define some cases where some letters in combination with each other form a certain sound. Hope this helps.

Answer 2

Since all you're really doing is check for patterns in the string, you could use a regular expression. This should also allow for future expansion of letter combos like lutge098 talked about:

public static string GetIndefinateArticle(string noun)
{
    if (Regex.Matches(noun, "^([aeio]|un|ul)", RegexOptions.IgnoreCase))
        return "an " + noun;
    else
        return "a " + noun;
}

Answer 3

If this is something you need done seriously, you may consider porting the Ruby Linguistics (English) library to .Net. It's open source & does a pretty good job of calculating the correct articles.

http://deveiate.org/projects/Linguistics/