C# Array of generic objects, indexable by string attribute. Need help.

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pwaddles

113 posts

Master Geek

Topic # 58729 17-Mar-2010 23:37

Hi guys,

Say I have a class Item, which has 2 attributes, ID : String and Description : String. I want to be able to make an array or list of Items and be able to index it on the ID which is a string.

I've had a look at Arrays, Lists, Collections, ArrayLists but cant find anything that will let me do what I need it to do.

Im pretty new to C#, and this wasnt covered in the course I took.

Essentially I need what Jade calls a MemberKeyDictionary but in C#.

Is this possible?

Cheers

Pwaddles

Regs

Infrastructure Geek
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Reply # 308562 17-Mar-2010 23:51

you need to include the IEnumerator in your class. Something like this which was cut out of some inelegant code i wrote once:

public class MyObjectList
{
public MyObject[] MyObjectList = new MyObject[0];

public IEnumerator GetEnumerator()
{
return (MyObjectList as IEnumerable).GetEnumerator();
}

public void AddMyObject(MyObject NewItem){
Array.Resize(ref MyObjectList, MyObjectList.Length + 1);
MyObjectList[MyObjectList.Length -1] = NewItem;
}
}

PS. i'm not a C# guru..... those who are please step in and offer advice or criticism!

PPS. Google up IEnumerator and C# and you'll probably find some useful articles

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Regs

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Reply # 308565 17-Mar-2010 23:58

i just googled exactly that "C# ienumerator" and the first couple of links do a much better job than me :P

http://www.c-sharpcorner.com/UploadFile/prasadh/Enumerators11132005232321PM/Enumerators.aspx
http://www.devarticles.com/c/a/C-Sharp/Interface-IEnumerable-and-IEnumerator-in-C-sharp/

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davidcole

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Reply # 308602 18-Mar-2010 08:36

You could look at:
System.Collections.Generic.SortedList<string,yourObjecttype> myArray = new System.Collections.Generic.SortedList<string,yourObjecType>();

EDIT: There should be greater than and less than signs around the string and yourobjecttype - but the editor seems to kill them

And create a struct for you objects with the two attributes.

This will create a sorted list collection with strongly typed objects.

Then to enumerate the collection of values you can go:
foreach (YourObjectType myObject in myArray.Values)
{
Do stuff here
}

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