ToStringIfNotNull; allows me to write `return o.ToStringIfNotNull();` instead of `return o==null?null:o.ToString();` ; i.e. a ToString function which can cope with null references.

CSharpGeneralHelperFunctions

 public static class ObjectExtensions
    {
        public static string ToStringIfNotNull(this object o)
        {
            return o == null ? null : o.ToString();
        }
    }