Automapper resolveusing not returning nulls - asp.net-mvc-4

Question

I'm working on an MVC 4 project and trying to convert a value in a KeyValue list to a nullable DateTime. I have used the following line in the mapper (I've not included the other properties as there are a lot)
.ForMember(d => d.Deadline, m => m.ResolveUsing<DeadlineResolver>())
My resolver looks like this:
public class DeadlineResolver : ValueResolver<Booking, DateTime?>
{
protected override DateTime? ResolveCore(Booking source, ResolutionResult resolutionResult)
{
KeyValue keyValue = source.KeyValues.FirstOrDefault(k => k.Key.KeyId == "DEADLINE");
return (keyValue != null) ? DateTime.Parse(keyValue.Value) : (DateTime?)null;
}
}
The value of deadline which is defined as shown below is never returned as null but DateTime.MinDate instead. I need it to be null when I'm the binding the result in a view so that I only show a value when there is a date.
public DateTime? Deadline { get; set; }
How do I make these values null without going over the values after mapping to look for min dates and set to null (temp hack I've put in place so the code runs)?

Answer 1

Using LinqPad and AutoMapper 2.2.1 the following gives me a valid date when KeyValue has a date, and a null DateTime when KeyValue is null. (Note there are minor changes to the resolver to simplify it as the class definitions weren't provided).
void Main()
{
AutoMapper.Mapper.CreateMap<Booking, dest>()
.ForMember(d => d.Deadline, m => m.ResolveUsing<DeadlineResolver>());
AutoMapper.Mapper.AssertConfigurationIsValid();
// Gives a valid DateTime
var booking = new Booking { KeyValue = "2013-01-01" };
booking.Dump();
var rc = AutoMapper.Mapper.Map<Booking, dest>(booking);
rc.Dump();
// Gives a null DateTime
booking = new Booking { KeyValue = null };
booking.Dump();
rc = AutoMapper.Mapper.Map<Booking, dest>(booking);
rc.Dump();
}
// Define other methods and classes here
public class Booking
{
public string KeyValue { get; set; }
}
public class dest
{
public DateTime? Deadline { get; set; }
}
public class DeadlineResolver : AutoMapper.ValueResolver<Booking, DateTime?>
{
protected override DateTime? ResolveCore(Booking source)
{
return (source.KeyValue != null)
? DateTime.Parse(source.KeyValue)
: (DateTime?)null;
}
}
Is this the functionality you were after? If so, then the issue could be with an older version of AutoMapper, or an unexpected KeyValue value.