472,958 Members | 2,624 Online
Bytes | Software Development & Data Engineering Community
Post Job

Home Posts Topics Members FAQ

Join Bytes to post your question to a community of 472,958 software developers and data experts.

Inheriting from CollectionBase

I wanted to create a type-safe collection by inheriting from CollectionBase.

Public Class MyCollection : Inherits CollectionBase

I found that IList.Add did not allow the setting of a "key" to identify an
object added to the collection.
So to implement a "key" similar to the parameter allowed by the standard
Collection object do I have to create my own array to store the "keys" and
manage it within my class MyCollection? I can't see how I will be able to
make sure my array of "keys" will always point to the correct items in the
collection.
Seems a headache, would like to know if there is some other class I can
inherit from to gain methods more similar to that of Collection.

--
Thanks for any help,
Shayne H
Nov 20 '05 #1
2 3995
Shayne,
If you want to store elements by key, you should inherit from
DictionaryBase.

If you want to index elements by both key & integer, then I would suggest
inheriting from System.Collections.Specialized.NameObjectCollectio nBase.

Hope this helps
Jay

"Shayne H" <shaynehATlycosSPAMGOTOHELLcoDOTuk> wrote in message
news:%2******************@tk2msftngp13.phx.gbl...
I wanted to create a type-safe collection by inheriting from CollectionBase.
Public Class MyCollection : Inherits CollectionBase

I found that IList.Add did not allow the setting of a "key" to identify an
object added to the collection.
So to implement a "key" similar to the parameter allowed by the standard
Collection object do I have to create my own array to store the "keys" and
manage it within my class MyCollection? I can't see how I will be able to
make sure my array of "keys" will always point to the correct items in the
collection.
Seems a headache, would like to know if there is some other class I can
inherit from to gain methods more similar to that of Collection.

--
Thanks for any help,
Shayne H

Nov 20 '05 #2
Thanks a heap
Nov 20 '05 #3

This thread has been closed and replies have been disabled. Please start a new discussion.

Similar topics

5
by: Steve M | last post by:
I have subclassed CollectionBase. I have also implemented GetEnumerator(). I have tried to set the DataSource of a DataGrid to an instance of my subclass. However, the items in the grid are not...
7
by: m. pollack | last post by:
Hi all, I've been using the CollectionBase class to implement a strongly-typed collection, but I have noticed that the RemoveAt method does not seem to call the "On" hook methods (OnRemove,...
11
by: Noah Coad [MVP .NET/C#] | last post by:
How do you make a member of a class mandatory to override with a _new_ definition? For example, when inheriting from System.Collections.CollectionBase, you are required to implement certain...
5
by: Eric Johannsen | last post by:
I have a simple object that inherits from CollectionBase and overrides the Count property: namespace MyTest { public class CollTest : System.Collections.CollectionBase { public override int...
2
by: Scott Reynolds | last post by:
I am having a problem exposing a class inherited from the collection base class as a webservice. If I expose the collection on a web page all works well and I am very happy. However when I try and...
2
by: Mark Overstreet | last post by:
I am writing custom collections for my business objects but I need support for the foreach construct. I also need key support so I am inheriting from NameObjectCollectionBase. I need to support...
1
by: Matthew Roberts | last post by:
Howdy Everyone, I am having trouble understanding the process of creating a type-safe collection by inheriting from the CollectionBase class. I have done it plenty of times, but now that I sit...
1
by: Kyle Novak | last post by:
I have a question about strongly typed objects when looping through a collection based on the CollectionBase object and using a For..Each loop. I have 2 objects: -Invoice: Holds all properties...
5
by: jc | last post by:
RE: Two Classes with the same Data Structure.. saving code? Inheriting a structure? I have two classes. One in Inherits System.Collections.CollectionBase, the other does not, but they both have...
3
by: Tony Johansson | last post by:
Hello! Sorry for opening up this task again. I want to fully understand this List that is return from CollectionBase. According to you is List in CollectionBase implemented something like...
2
by: DJRhino | last post by:
Was curious if anyone else was having this same issue or not.... I was just Up/Down graded to windows 11 and now my access combo boxes are not acting right. With win 10 I could start typing...
0
tracyyun
by: tracyyun | last post by:
Hello everyone, I have a question and would like some advice on network connectivity. I have one computer connected to my router via WiFi, but I have two other computers that I want to be able to...
2
by: giovanniandrean | last post by:
The energy model is structured as follows and uses excel sheets to give input data: 1-Utility.py contains all the functions needed to calculate the variables and other minor things (mentions...
1
by: Teri B | last post by:
Hi, I have created a sub-form Roles. In my course form the user selects the roles assigned to the course. 0ne-to-many. One course many roles. Then I created a report based on the Course form and...
0
isladogs
by: isladogs | last post by:
The next Access Europe meeting will be on Wednesday 1 Nov 2023 starting at 18:00 UK time (6PM UTC) and finishing at about 19:15 (7.15PM) Please note that the UK and Europe revert to winter time on...
3
by: nia12 | last post by:
Hi there, I am very new to Access so apologies if any of this is obvious/not clear. I am creating a data collection tool for health care employees to complete. It consists of a number of...
0
NeoPa
by: NeoPa | last post by:
Introduction For this article I'll be focusing on the Report (clsReport) class. This simply handles making the calling Form invisible until all of the Reports opened by it have been closed, when it...
0
isladogs
by: isladogs | last post by:
The next online meeting of the Access Europe User Group will be on Wednesday 6 Dec 2023 starting at 18:00 UK time (6PM UTC) and finishing at about 19:15 (7.15PM). In this month's session, Mike...
2
by: GKJR | last post by:
Does anyone have a recommendation to build a standalone application to replace an Access database? I have my bookkeeping software I developed in Access that I would like to make available to other...

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.