How to implement an age display helper in C#

Here is a snippet for formatting age display. You can expand on this helper to suit your needs.

I implemented this helper for a client wanted to hide the age of users who were younger than 14 years.

public static string AgeDisplay(this HtmlHelper helper, DateTime birthday) {
    var now = DateTime.Today;
    var age = now.Year - birthday.Year;
    var result = "";
    if (now < birthday.AddYears(age)) age--;
    if (age >= 14)   // Dont display age, of any users who are younger then 14 years old.
    {
        result = age + "years old, ";
    }
    return result;
}