Why isn't there a Guid.IsNullOrEmpty() method

Question

This keeps me wondering why Guid in .NET does not have IsNullOrEmpty() method (where empty means all zeros)

I need this at several places in my ASP.NET

Answer 1

Here is a generic extension class for nullable struct types:

public static class NullableExtensions
{
    public static bool IsNullOrDefault(this T? self) where T : struct
    {
        return !self.HasValue || self.Value.Equals(default(T));
    }
}