Can I have a class within a class in C#

Question

I have the following class:

public class NoteLink
{

    public IList<NoteLinkDetail> NoteLinkDetails
    {
        get { return _noteLinkDetails; }
    }
    private List<NoteLinkDetail> _noteLinkDetails = new List<NoteLinkDetail>();

    public NoteLink()
    {
        _noteLinkDetails = new List<NoteLinkDetail>();
    }

}

and then another class that's used just within the first class.

public class NoteLinkDetail
{
    public string L { get; set; }
    public string R { get; set; }
}

Is there anything I could do to optimize this. I DO need the second class as I use JSON to store the contents of NoteLinkDetail in a string. However is there such a thing as an inner class in C#? Any recommendation on how I could optimize this code? Thanks.

Yes, there are inner classes in C#. [See this answer on SO for more details.](http://stackoverflow.com/questions/804453/using-inner-classes-in-c) — Peter K., Jul 27 '11 at 17:02

score 8 · Accepted Answer · answered Jul 27 '11 at 17:01

Yes, you can. Just nest it.

public class NoteLink
{
    // ...

    public NoteLink()
    {
        _noteLinkDetails = new List<NoteLinkDetail>();
    }

    public class NoteLinkDetail
    {
        public string L { get; set; }
        public string R { get; set; }
    }
}

Moreover, if it is not exposed outside the outer class, your inner class can even be private and stay invisible to outer class users.

score 3 · Answer 2 · answered Jul 27 '11 at 17:01

3

Yes, C# allows nested classes.

C# nested classes are much more like nested classes in C++ than "inner classes" in Java. This link explains:

http://blogs.msdn.com/b/oldnewthing/archive/2006/08/01/685248.aspx

answered Jul 27 '11 at 17:01

paulsm4

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score 1 · Answer 3 · answered Jul 27 '11 at 17:02

1

Sure; just declare the inner class from within the outer class

class NoteLink
{
    class NoteLinkDetail
    {

    }
}

answered Jul 27 '11 at 17:02

Ed S.

122,712
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But then how do I call that class externally because I need to do some JSON work on the inner class to serialize it? – Bianca Jul 27 '11 at 17:09
NoteLink.NoteLinkDetail detail = new NoteLink.NoteLinkDetail – Kyle W Jul 27 '11 at 17:17

score 0 · Answer 4 · answered Jul 27 '11 at 17:02

0

Yes, you can have nested classes in C#

answered Jul 27 '11 at 17:02

james_bond

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Can I have a class within a class in C#

4 Answers4