private Expression CreateMapExpressionCore(ExpressionRequest request, Expression instanceParameter, TypePairCount typePairCount, TypeMap typeMap, LetPropertyMaps letPropertyMaps)
{
var bindings = new List <MemberBinding>();
var depth = GetDepth(request, typePairCount);
if (typeMap.MaxDepth > 0 && depth >= typeMap.MaxDepth)
{
if (typeMap.Profile.AllowNullDestinationValues)
{
return(null);
}
}
else
{
bindings = CreateMemberBindings(request, typeMap, instanceParameter, typePairCount, letPropertyMaps);
}
Expression constructorExpression = DestinationConstructorExpression(typeMap, instanceParameter);
if (instanceParameter is ParameterExpression)
{
constructorExpression = ((LambdaExpression)constructorExpression).ReplaceParameters(instanceParameter);
}
var visitor = new NewFinderVisitor();
visitor.Visit(constructorExpression);
var expression = MemberInit(
visitor.NewExpression,
bindings.ToArray()
);
return(expression);
}
private static int GetDepth(ExpressionRequest request, TypePairCount typePairCount)
{
if (typePairCount.TryGetValue(request, out int visitCount))
{
visitCount = visitCount + 1;
}
typePairCount[request] = visitCount;
return(visitCount);
}
private List <MemberBinding> CreateMemberBindings(ExpressionRequest request, TypeMap typeMap, Expression instanceParameter, TypePairCount typePairCount, LetPropertyMaps letPropertyMaps)
{
var bindings = new List <MemberBinding>();
foreach (var propertyMap in typeMap.PropertyMaps
.Where(pm => (!pm.ExplicitExpansion || request.MembersToExpand.Contains(pm.DestinationMember)) &&
pm.CanResolveValue && ReflectionHelper.CanBeSet(pm.DestinationMember))
.OrderBy(pm => pm.DestinationName))
{
var propertyExpression = new PropertyExpression(propertyMap);
letPropertyMaps.Push(propertyExpression);
CreateMemberBinding(propertyExpression);
letPropertyMaps.Pop();
}
return(bindings);
void CreateMemberBinding(PropertyExpression propertyExpression)
{
var propertyMap = propertyExpression.PropertyMap;
var result = ResolveExpression(propertyMap, request.SourceType, instanceParameter, letPropertyMaps);
propertyExpression.Expression = result.ResolutionExpression;
var propertyTypeMap = _configurationProvider.ResolveTypeMap(result.Type, propertyMap.DestinationType);
var propertyRequest = new ExpressionRequest(result.Type, propertyMap.DestinationType, request.MembersToExpand, request);
if (propertyRequest.AlreadyExists)
{
return;
}
var binder = _configurationProvider.Binders.FirstOrDefault(b => b.IsMatch(propertyMap, propertyTypeMap, result));
if (binder == null)
{
var message =
$"Unable to create a map expression from {propertyMap.SourceMember?.DeclaringType?.Name}.{propertyMap.SourceMember?.Name} ({result.Type}) to {propertyMap.DestinationMember.DeclaringType?.Name}.{propertyMap.DestinationName} ({propertyMap.DestinationType})";
throw new AutoMapperMappingException(message, null, typeMap.Types, typeMap, propertyMap);
}
var bindExpression = binder.Build(_configurationProvider, propertyMap, propertyTypeMap, propertyRequest, result, typePairCount, letPropertyMaps);
if (bindExpression == null)
{
return;
}
var rhs = propertyMap.ValueTransformers
.Concat(typeMap.ValueTransformers)
.Concat(typeMap.Profile.ValueTransformers)
.Where(vt => vt.IsMatch(propertyMap))
.Aggregate(bindExpression.Expression, (current, vtConfig) => ToType(ReplaceParameters(vtConfig.TransformerExpression, ToType(current, vtConfig.ValueType)), propertyMap.DestinationType));
bindExpression = bindExpression.Update(rhs);
bindings.Add(bindExpression);
}
}
private Expression CreateMapExpressionCore(ExpressionRequest request, Expression instanceParameter, TypePairCount typePairCount, LetPropertyMaps letPropertyMaps, out TypeMap typeMap)
{
typeMap = _configurationProvider.ResolveTypeMap(request.SourceType, request.DestinationType);
if (typeMap == null)
{
throw QueryMapperHelper.MissingMapException(request.SourceType, request.DestinationType);
}
if (typeMap.CustomMapExpression != null)
{
return(typeMap.CustomMapExpression.ReplaceParameters(instanceParameter));
}
return(CreateMapExpressionCore(request, instanceParameter, typePairCount, typeMap, letPropertyMaps));
}
public LambdaExpression[] CreateMapExpression(ExpressionRequest request, TypePairCount typePairCount, LetPropertyMaps letPropertyMaps)
{
// this is the input parameter of this expression with name <variableName>
var instanceParameter = Parameter(request.SourceType, "dto" + request.SourceType.Name);
var expressions = new QueryExpressions(CreateMapExpressionCore(request, instanceParameter, typePairCount, letPropertyMaps, out var typeMap));
if (letPropertyMaps.Count > 0)
{
expressions = letPropertyMaps.GetSubQueryExpression(this, expressions.First, typeMap, request, instanceParameter, typePairCount);
}
if (expressions.First == null)
{
return(null);
}
var firstLambda = Lambda(expressions.First, instanceParameter);
if (expressions.Second == null)
{
return(new[] { firstLambda });
}
return(new[] { firstLambda, Lambda(expressions.Second, expressions.SecondParameter) });
}
private LambdaExpression[] CreateMapExpression(ExpressionRequest request) => CreateMapExpression(request, new Dictionary <ExpressionRequest, int>(),
new FirstPassLetPropertyMaps(_configurationProvider)
);
public Expression CreateMapExpression(ExpressionRequest request, Expression instanceParameter, TypePairCount typePairCount, LetPropertyMaps letPropertyMaps)
{
return(CreateMapExpressionCore(request, instanceParameter, typePairCount, letPropertyMaps, out var _));
}
public MemberAssignment Build(IConfigurationProvider configuration, PropertyMap propertyMap, TypeMap propertyTypeMap, ExpressionRequest request, ExpressionResolutionResult result, IDictionary <ExpressionRequest, int> typePairCount, LetPropertyMaps letPropertyMaps)
{
var defaultDestination = Activator.CreateInstance(propertyMap.DestinationType);
return(Bind(propertyMap.DestinationMember, Coalesce(result.ResolutionExpression, Constant(defaultDestination))));
}
