Accessing nonstatic member of outer class

Question

Is there anyway to access nonstatic member (either method or variable) of outer class from nested (inner) class? Here is the example: public class outer { public string st = ""; public class inner { //here I need to access the st string without declaring st as static } } I could, of course, create a new object of type outer and refer the st variable using that object, like myOuter.st but then I think I just create a new instance of st. Please suggest. Thanks.

david 0 · Answer

public class Outter { public class Inner { public Inner(Outter wrap) { m_Wrap = wrap; } private Outter m_Wrap; public void IDo() { m_Wrap.YouDont(); } } public Outter() { Inner i = new Inner(this); i.IDo(); } public void YouDont() { } }

scott.hayman · Answer

Thank you. I think I know what you mean however (being a rookie) could you make a more concrete example?

david 0 · Answer

The need for nested classes is indeed rare but definately exists for special purposes. When the inner needs to be able to access instance data of the outer it is conventional to pass an instance reference as part of the constructor.

scott.hayman · Answer

Actually... Thank all of you for this posting. I'm a beginning developer (C#) and have been looking at how to create a master-detail structure or collection. An example would be like order - order item type of system where the order number would be the common property. From this posting I can see that nesting classes would not be the best way of implementing this. Thanks again.

chrishornberger · Answer

Rain... general rule of thumb is only to use inner classes when: 1) the outer class is the only consumer 2) the outer class is the only constructor/factory of those classes

katana · Answer

I'm confused. Perhaps I'm just not thinking cuz it is late. But why would you need an inner and outer class? Why have an outer class anyways? Perhaps I'm just being dumb but I don't see a reason. I think you just instanitate a outer myOuter = new outer(); myOuter.st; I think that would be the easiest way. I'm still confused as to the reason of why you would do that.