private Expression BindSelect(Type resultType, Expression source, LambdaExpression selector)
{
MetaProjectorExpression mp = AsProjection(Visit(source));
Expression projector = MapAndVisit(selector, mp);
return(new MetaProjectorExpression(resultType, projector));
}
protected virtual Expression BindJoin(Type resultType, Expression outerSource, Expression innerSource, LambdaExpression outerKey, LambdaExpression innerKey, LambdaExpression resultSelector)
{
MetaProjectorExpression mpOuter = AsProjection(Visit(outerSource));
MetaProjectorExpression mpInner = AsProjection(Visit(innerSource));
Expression projector = MapAndVisit(resultSelector, mpOuter, mpInner);
return(new MetaProjectorExpression(resultType, projector));
}
private Expression BindGroupBy(Type resultType, Expression source, LambdaExpression keySelector, LambdaExpression elementSelector)
{
MetaProjectorExpression mp = AsProjection(Visit(source));
Expression key = MapAndVisit(keySelector, mp);
Expression element = MapAndVisit(elementSelector, mp);
Type colType = typeof(IEnumerable <>).MakeGenericType(element.Type);
Type groupType = typeof(Grouping <,>).MakeGenericType(key.Type, element.Type);
return(new MetaProjectorExpression(resultType,
Expression.New(groupType.GetConstructor(new Type[] { key.Type, colType }) !,
key, new MetaProjectorExpression(colType, element))));
}
private Expression BindAggregate(Type resultType, AggregateSqlFunction aggregateFunction, Expression source, LambdaExpression?selector)
{
MetaProjectorExpression mp = AsProjection(Visit(source));
if (selector == null)
{
return(mp.Projector);
}
Expression projector = MapAndVisit(selector, mp);
return(projector);
}
protected virtual Expression BindSelectMany(Type resultType, Expression source, LambdaExpression collectionSelector, LambdaExpression?resultSelector)
{
MetaProjectorExpression mp = AsProjection(Visit(source));
MetaProjectorExpression collectionProjector = AsProjection(MapAndVisit(collectionSelector, mp));
if (resultSelector == null)
{
return(collectionProjector);
}
Expression resultProjection = MapAndVisit(resultSelector, mp, collectionProjector);
return(new MetaProjectorExpression(resultType, resultProjection));
}
