NHibernate Criteria Filtering - nhibernate

Question

I use this code to filter database records
if (!string.IsNullOrEmpty(_searchCriteria.MessageType))
{
var messageType = (AutotransferMessageType)Enum.Parse(typeof(AutotransferMessageType), _searchCriteria.MessageType, true);
if (Enum.IsDefined(typeof(AutotransferMessageType), messageType))
{
criteriaQuery.CreateAlias("AutotransferInputRecord", "AutotransferInputRecord")
.Add(
Restrictions.Eq(
"AutotransferInputRecord." + AutotransferLogSearchCriteria.MessageTypePropertyName,
messageType));
}
else
{
criteriaQuery.Add(Restrictions.IsNull("AutotransferInputRecord"));
}
}
AutotransferMessageType is enumerable type
public enum AutotransferMessageType
{
[DisplayName("MT202")]
[DatabaseName("MT202")]
MT202,
[DisplayName("MT210")]
[DatabaseName("MT210")]
MT210,
//...
}
My filter outputs the results when I enter MT202, for example. (It's the right behavior).
When I input just number, for example, 202, I get no results (It's the right behavior too).
But when I try to input some line, "mt", for example, I get error
Unexpected application error has been occured:
'Requested value 'mt' was not found.'
How to make the filter do not show any results when I input a line?

Answer 1

Your error is coming from the line that parses the enum. Use Enum.TryParse instead:
AutotransferMessageType msgEnum;
var enumPrasedOk = Enum.TryParse(_searchCriteria.MessageType, true, out msgEnum);
if(enumPrasedOk){
//Do something
}else{
//Handle case where enum was not found for some reason (if need be)
}
Also please note that you can not look up the enum this way using it's description (in your case they are the same so it is ok).