protected override Expression VisitMemberInit(MemberInitExpression node)
{
ODataExpansionOptions expansion = expansions.First();
if (node.NewExpression.Type != expansion.ParentType)
{
return(base.VisitMemberInit(node));
}
return(Expression.MemberInit
(
Expression.New(node.Type),
node.Bindings.OfType <MemberAssignment>().Aggregate
(
new List <MemberBinding>(),
AddBinding
)
));
List <MemberBinding> AddBinding(List <MemberBinding> list, MemberAssignment binding)
{
if (ListTypesAreEquivalent(binding.Member.GetMemberType(), expansion.MemberType) &&
string.Compare(binding.Member.Name, expansion.MemberName, true) == 0) //found the expansion
{
if (foundExpansions.Count > 0)
{
throw new NotSupportedException("Recursive queries not supported");
}
AddBindingExpression(GetBindingExpression(binding, expansion));
}
else
{
list.Add(binding);
}
return(list);
void AddBindingExpression(Expression bindingExpression)
{
list.Add(Expression.Bind(binding.Member, bindingExpression));
foundExpansions.Add(bindingExpression);
}
}
}
protected override Expression GetBindingExpression(MemberAssignment binding, ODataExpansionOptions expansion)
{
if (expansion.FilterOptions != null)
{
return(FilterAppender.AppendFilter(binding.Expression, expansion));
}
else if (expansions.Count > 1) //Mutually exclusive with expansion.Filter != null.
{ //There can be only one filter in the list. See the GetFilters() method in QueryableExtensions.UpdateQueryable.
return(UpdaterExpansion
(
binding.Expression,
expansions.Skip(1).ToList()
));
}
else
{
throw new ArgumentException("Last expansion in the list must have a filter", nameof(expansions));
}
}
protected abstract Expression GetBindingExpression(MemberAssignment binding, ODataExpansionOptions expansion);
public static Expression AppendQueryMethod(Expression expression, ODataExpansionOptions expansion) => new MethodAppender(expression, expansion).Visit(expression);
public MethodAppender(Expression expression, ODataExpansionOptions expansion)
{
this.expansion = expansion;
this.expression = expression;
}
public FilterAppender(Expression expression, ODataExpansionOptions expansion)
{
this.expansion = expansion;
this.expression = expression;
}
public static Expression AppendFilter(Expression expression, ODataExpansionOptions expansion) => new FilterAppender(expression, expansion).Visit(expression);
