// Constructors
public ProjectionExpression(
Type type,
ItemProjectorExpression itemProjectorExpression,
Dictionary <Parameter <Tuple>, Tuple> tupleParameterBindings)
: this(type, itemProjectorExpression, tupleParameterBindings, ResultAccessMethod.All)
{
}
public ProjectionExpression(
Type type,
ItemProjectorExpression itemProjectorExpression,
Dictionary <Parameter <Tuple>, Tuple> tupleParameterBindings,
ResultAccessMethod resultAccessMethod)
: base(ExtendedExpressionType.Projection, type)
{
ItemProjector = itemProjectorExpression;
ResultAccessMethod = resultAccessMethod;
TupleParameterBindings = new Dictionary <Parameter <Tuple>, Tuple>(tupleParameterBindings);
}
public virtual Expression Remap(int[] map, Dictionary <Expression, Expression> processedExpressions)
{
// Don't check CanRemap - Remap always.
// Save Subquery parameter
var remapContext = RemapScope.CurrentContext;
bool isTopSubquery = remapContext.SubqueryParameterExpression == null;
if (isTopSubquery)
{
remapContext.SubqueryParameterExpression = OuterParameter;
}
// Remap recordset parameters
var visitor = new ApplyParameterAccessVisitor(ApplyParameter, (mc, index) => Call(mc.Object, mc.Method, Constant(map.IndexOf(index))));
var providerVisitor = new CompilableProviderVisitor((provider, expression) => visitor.Visit(expression));
var newDataSource = providerVisitor.VisitCompilable(ProjectionExpression.ItemProjector.DataSource);
// Remap Field parametrized parameters
var item = GenericExpressionVisitor <IMappedExpression> .Process(ProjectionExpression.ItemProjector.Item, mapped => {
var parametrizedExpression = mapped as ParameterizedExpression;
if (parametrizedExpression != null && parametrizedExpression.OuterParameter == OuterParameter)
{
return(mapped.Remap(map, new Dictionary <Expression, Expression>()));
}
return((Expression)mapped);
});
var newItemProjector = new ItemProjectorExpression(item, newDataSource, ProjectionExpression.ItemProjector.Context);
var newProjectionExpression = new ProjectionExpression(ProjectionExpression.Type, newItemProjector, ProjectionExpression.TupleParameterBindings);
var result = new SubQueryExpression(Type, OuterParameter, DefaultIfEmpty, newProjectionExpression, ApplyParameter, ExtendedType);
processedExpressions.Add(this, result);
// Restore subquery parameter
if (isTopSubquery)
{
remapContext.SubqueryParameterExpression = null;
}
return(result);
}
