private static object MapTypes(Type sourceType,
Type targetType,
PropertyMapInfo[] propertyMapInfos,
IMapperConfigurationExpression mapperConfiguration)
{
var createMapMethodInfo = GenericCreateMap.MakeGenericMethod(sourceType, targetType);
//actually create the mapping
var mapObject = createMapMethodInfo.Invoke(mapperConfiguration, new object[] { });
Debug.WriteLine($"Mapping created for source type {sourceType.Name} to target type {targetType.Name}");
var mapObjectExpression = Expression.Constant(mapObject);
var sourceTypeParameter = Expression.Parameter(sourceType);
foreach (var propMapInfo in propertyMapInfos)
{
var sourcePropertyInfos = propMapInfo.SourcePropertyInfos;
var targetPropertyInfo = propMapInfo.TargetPropertyInfo;
var targetPropertyName = targetPropertyInfo.Name;
Debug.WriteLine($"-- Mapping property {string.Join(".", sourcePropertyInfos.Select(s => s.Name))} to target type {targetPropertyName}");
var finalSourcePropertyType = sourcePropertyInfos.Last().PropertyType;
var memberConfigType = typeof(IMemberConfigurationExpression <, ,>)
.MakeGenericType(sourceType, targetType, typeof(object));
var memberConfigTypeParameter = Expression.Parameter(memberConfigType);
var propertyExpression =
sourcePropertyInfos.Aggregate <PropertyInfo, Expression>(null, (current, prop) => current == null
? Expression.Property(sourceTypeParameter, prop)
: Expression.Property(current, prop));
var memberOptions = Expression.Call(memberConfigTypeParameter,
nameof(IMemberConfigurationExpression.MapFrom),
new Type[] { finalSourcePropertyType },
Expression.Lambda(
propertyExpression,
sourceTypeParameter
));
var lambdaExpression = Expression.Lambda(memberOptions, memberConfigTypeParameter);
var forMemberMethodExpression =
Expression.Call(
mapObjectExpression,
nameof(IMappingExpression <object, object> .ForMember),
Type.EmptyTypes,
Expression.Constant(targetPropertyInfo.Name),
lambdaExpression);
//TODO: cache this somewhere for better repeat performance
Expression.Lambda(forMemberMethodExpression).Compile().DynamicInvoke();
}
return(mapObject);
}
internal static object MapTypes(Type sourceType,
Type targetType,
PropertyMapInfo[] propertyMapInfos,
IMapperConfigurationExpression mapperConfiguration)
{
var createMapMethodInfo = GenericCreateMap.MakeGenericMethod(sourceType, targetType);
//actually create the mapping
var mappingExpression = createMapMethodInfo.Invoke(mapperConfiguration, new object[] { });
Debug.WriteLine($"Mapping created for source type {sourceType.Name} to target type {targetType.Name}");
var mapObjectExpression = MapProperties(sourceType, targetType, propertyMapInfos, mappingExpression);
Expression.Lambda(mapObjectExpression).Compile().DynamicInvoke();
return(mappingExpression);
}