public Expression <Func <TSource, TDestination> > CombineIntoMapperWithConstructor(
Expression <Func <TSource, TDestination> > recipientExpression,
Expression <Func <TSource, TDestination> > donorExpression)
{
var paramReplacer = new ParameterReplacerVisitor(
donorExpression.Parameters[0],
recipientExpression.Parameters[0]);
var donorWithCorrectedParam = (Expression <Func <TSource, TDestination> >)paramReplacer.Visit(donorExpression);
var visitor = new MemberInitBindingsCombinationVisitor <TSource, TDestination>()
{
recipientExpression = recipientExpression,
donorExpression = donorWithCorrectedParam
};
var combinedExpr = (Expression <Func <TSource, TDestination> >)visitor.Visit(recipientExpression);
return(combinedExpr);
}
public Expression <Action <TSource, TDestination> > CombineIntoMapperForExisting(
Expression <Func <TSource, TDestination> > expressionA,
Expression <Func <TSource, TDestination> > expressionB)
{
var bindingsA = MemberInitBindingsCombinationVisitor <TSource, TDestination> .GetBindings(expressionA);
var bindingsB = MemberInitBindingsCombinationVisitor <TSource, TDestination> .GetBindings(expressionB);
var paramDestination = Expression.Parameter(typeof(TDestination), "destination");
var paramSource = Expression.Parameter(typeof(TSource), "source");
BinaryExpression GetAssignment(ParameterExpression paramSourceExisting, MemberBinding binding)
{
var assignment = MemberInitBindingsCombinationVisitor <TSource, TDestination>
.GetAssignmentFromBinding(binding,
paramSourceExisting,
paramSource,
paramDestination);
return(assignment);
}
var assignmentsA = bindingsA
.Select(binding =>
GetAssignment(expressionA.Parameters[0], binding));
var assignmentsB = bindingsB
.Select(binding =>
GetAssignment(expressionB.Parameters[0], binding));
var combinedAssignments = assignmentsA
.Union(assignmentsB)
.ToArray();
var body = Expression.Block(combinedAssignments);
return(Expression.Lambda <Action <TSource, TDestination> >(body, new[] { paramSource, paramDestination }));
}
