>>>Hi,
>>>
>>>I've used the Business Layer Generator and it has generated a rule like this for a field:
>>>
>>>

		/// <summary>
>>>		/// Validates the Min Age
>>>		/// </summary>
>>>		public string ValidateMinAge(byte minAge)
>>>		{
>>>			string Msg = null;
>>>			if (mmType.IsEmpty(minAge))
>>>			{
>>>				this.EntityPropertyDisplayName = "Minimum Age";
>>>
>>>				Msg = this.RequiredFieldMessagePrefix + 
>>>					this.EntityPropertyDisplayName + 
>>>					this.RequiredFieldMessageSuffix;
>>>
>>>				AddErrorProviderBrokenRule("MinAge",  Msg);
>>>			}
>>>			return Msg;
>>>		}

>>>
>>>This causes a zero value to be invalid. What do I do to disallow null values but allow a zero value?
>>
>>Frank, that method gets the proposed value passed in and checks if it is empty. You can modify this method anyway you want to check it and set the return message for a broken rule the way you want also. Why is age a byte type?
>Maybe because MinAge is in years and refers to something that won't last for 256 of them :-}

Well, I just learned something and it unfortunately isn't that I won't live that long.
Thanks
Tim