public void ReflectiveVisit(VisitorElement element)
{
// Use reflection to find and invoke the correct Visit method
Type[] types = new Type[] { element.GetType() };
MethodInfo methodInfo = this.GetType().GetMethod("Visit", types);
if (methodInfo != null)
methodInfo.Invoke(this, new object[] { element });
else Console.WriteLine("Unexpected Visit");
}
static void Main()
{
// Set up the object structure
VisitorElement objectStructure =
new VisitorElement(
new VisitorElement(
new ElementWithLink(
new VisitorElement(
new VisitorElement(
new ElementWithLink(
new VisitorElement(null),
new VisitorElement(
null)))),
new VisitorElement(
new VisitorElement(
new VisitorElement(null))))));
Console.WriteLine("Count the elements");
CountVisitor visitor = new CountVisitor();
visitor.CountElements(objectStructure);
Console.WriteLine("Number of Elements is: " + visitor.Count);
}
// Only Elements are counted
public void Visit(VisitorElement element)
{
Count++;
}
public void CountElements(VisitorElement element)
{
ReflectiveVisit(element);
if (element.Part != null) CountElements(element.Part);
if (element.Next != null) CountElements(element.Next);
}
public ElementWithLink(VisitorElement part, VisitorElement next)
{
Next = next;
Part = part;
}
public VisitorElement(VisitorElement next)
{
Next = next;
}