public MappingStrategy(MappingInfo mappingInfo, IMappingDescriptor descriptor)
{
Descriptor = descriptor;
Source = mappingInfo.MappingSourceType;
Target = mappingInfo.MappingTargetType;
HasTargetInstance = mappingInfo.MapIntoExistingTargetInstance;
try
{
TargetConstructor = Target.GetConstructors().Single();
ConstructorParameterMappingSteps = new OrderedKeyedCollection <ParameterInfo, MappingStep>(TargetConstructor.GetParameters());
}
catch (InvalidOperationException)
{
throw new ArgumentException("Target type must have single public constructor. This is the only scenario supported at the moment.", "target");
}
ContextExpression = Expression.Parameter(typeof(MappingContext), "context");
SourceExpression = Expression.Variable(Source, "source");
TargetExpression = Expression.Variable(Target, "target");
MapperExpression = Expression.Property(ContextExpression, MappingContextMeta.Mapper);
}
public MappingStrategy BuildMappingStrategy(MappingInfo mappingInfo)
{
var strategy = new MappingStrategy(mappingInfo, descriptor);
//first try to shortcircuit
var directMappingStep = new DirectMappingStep(strategy.Source, strategy.Target);
var converter = ApplyConverter(directMappingStep, withFallback: false);
if (converter != null)
{
directMappingStep.Conversion = converter;
strategy.InitTargetStep = directMappingStep;
return(strategy);
}
foreach (var pattern in mappingPatterns)
{
pattern.Contribute(strategy);
}
foreach (var mappingStep in strategy.MappingSteps)
{
mappingStep.Conversion = ApplyConverter(mappingStep, withFallback: true);
}
if (strategy.HasTargetInstance)
{
strategy.InitTargetStep = new SimpleStep(strategy.Target, strategy.Target, (s, _) => Expression.Convert(Expression.Property(s.ContextExpression, MappingContextMeta.TargetInstance), s.Target));
}
else
{
foreach (var mappingStep in strategy.ConstructorParameterMappingSteps.ByKey)
{
if (mappingStep.Value == null)
{
throw new InvalidOperationException(string.Format("No mapping for constructor parameter {0} has been specified. All constructor parameters need value", mappingStep.Key));
}
mappingStep.Value.Conversion = ApplyConverter(mappingStep.Value, withFallback: true);
}
strategy.InitTargetStep = new SimpleStep(strategy.Target, strategy.Target, (s, _) => Expression.New(s.TargetConstructor, GetConstructorParameters(s)));
}
return(strategy);
}
public IIMappingBag Add(MappingInfo mappingInfo)
{
mappings.Add(mappingInfo);
return(this);
}