gistfile1.cs

public class FileIconDescriptor<T> : UIDescriptor<T> where T : ContentData
{
    public FileIconDescriptor()
    {
        Type type = GetType();
        string fileTypeName = type.BaseType.GetGenericArguments()[0].Name;
        IconClass = fileTypeName.Replace("File", "").ToLower() + "Icon";
    }
}