public HandlerAxis(IHandlerAxis handler, TraversingAxis axis)
{
if (handler == null)
{
throw new ArgumentNullException(nameof(handler));
}
_handler = handler;
_axis = axis;
}
public virtual bool Handle(
TraversingAxis axis, object callback,
bool greedy, IHandler composer)
{
if (axis == TraversingAxis.Self)
{
return(base.HandleCallback(callback, greedy, composer));
}
var handled = false;
Traverse(axis, node =>
{
handled = handled | (node == this
? BaseHandle(callback, greedy, composer)
: ((TContext)node).Handle(
TraversingAxis.Self, callback, greedy, composer));
return(handled && !greedy);
});
return(handled);
}
public static void Traverse(ITraversing node, TraversingAxis axis, Visitor visitor)
{
if (visitor == null)
{
return;
}
switch (axis)
{
case TraversingAxis.Self:
node.TraverseSelf(visitor);
break;
case TraversingAxis.Root:
node.TraverseRoot(visitor);
break;
case TraversingAxis.Child:
node.TraverseChildren(visitor, false);
break;
case TraversingAxis.Sibling:
node.TraverseSelfSiblingOrAncestor(visitor, false, false);
break;
case TraversingAxis.SelfOrChild:
node.TraverseChildren(visitor, true);
break;
case TraversingAxis.SelfOrSibling:
node.TraverseSelfSiblingOrAncestor(visitor, true, false);
break;
case TraversingAxis.Ancestor:
node.TraverseAncestors(visitor, false);
break;
case TraversingAxis.SelfOrAncestor:
node.TraverseAncestors(visitor, true);
break;
case TraversingAxis.Descendant:
node.TraverseDescendants(visitor, false);
break;
case TraversingAxis.DescendantReverse:
node.TraverseDescendantsReverse(visitor, false);
break;
case TraversingAxis.SelfOrDescendant:
node.TraverseDescendants(visitor, true);
break;
case TraversingAxis.SelfOrDescendantReverse:
node.TraverseDescendantsReverse(visitor, true);
break;
case TraversingAxis.SelfSiblingOrAncestor:
node.TraverseSelfSiblingOrAncestor(visitor, true, true);
break;
}
}
public static IHandlerAxis Axis(
this IHandlerAxis handler, TraversingAxis axis)
{
return(handler == null ? null
: new HandlerAxis(handler, axis));
}
public bool Handle(
TraversingAxis axis, object callback, bool greedy, IHandler composer)
{
return(_handler.Handle(axis, callback, greedy, composer));
}
public void Traverse(TraversingAxis axis, Visitor visitor)
{
TraversingHelper.Traverse(this, axis, visitor);
}
