Again, I was reading Guthrie’s blog and found his post on Extension Methods

What this allows a developer to do is extend types without needing to create a static service class. It is more like an extension class.


You want to add a method called IsValidEmailAddress to the base string class:

string email = Request.QueryString[“email”];

if ( email.IsValidEmailAddress() ) { }

You would create the following (the this keyword in the parameter list is the key)

public static class OrcasExtensions {    public static bool IsValidEmailAddress(this string s)    {       Regex regex = new Regex(@"^[w-.]+@([w-]+.)+[w-]{2,4}$");       return regex.IsMatch(s);    } }

Just add the following to your class:

using OrcasExtensions;