how can i creat variable number of lists

Question

0.00/5 (No votes)

See more:

Hello masters,

I want to ask if it is possible to create variable number of lists.

C#

public void CreateClusters(int NumberOfClusters)
       {
           for (int i = 1; i < NumberOfClusters ; i++)
           {
               List<Color> Cluster(i) = new List<Color>();
           }
       }

For example when the i is 1, i want to create a color list named "Cluster1"

I am new at programming and thank you for your help.

Posted 11-May-12 11:05am

Çağrı Daşkın

Add a Solution

2 solutions

Solution 1

This is two folded. Basically you can create new named variables on the fly by generating for example code that is then compiled. However, since you mentioned that you're new to programming, I would say that this is a wrong approach. Do you really need new variables or just new instances of a predefined class?

Based on the description you have given I suppose you want to separate different instances of Color in your list. Would a Dictionary[^] satisfy your requirements?

Posted 11-May-12 11:28am

Wendelius

Comments

VJ Reddy 12-May-12 0:27am

Dictionary is a good suggestion. 5!

Wendelius 12-May-12 4:15am

Thank you :)

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Sergey Alexandrovich Kryukov · Accepted Answer · 2012-05-11T11:28:00

Just use some simple logic. From your code, it looks like you should understand that a generic list is a collection of anything. So, what can act as a collection of variable number of lists? Not surprisingly, a list of lists:

C#

using ColorList = System.Collections.Generic.List<Color>;
using ListOfColorLists = System.Collections.Generic.List<System.Collections.Generic.List<Color>>;

//...

public ListOfColorLists CreateClusters(int numberOfClusters) {
    ListOfColorLists list = new ListOfColorLists();
    for (int index = 0; index < numberOfClusters; ++index)
        list.Add(new ColorList());
    return list;
} //CreateClusters

Please pay attention for some fixed I've made. First of all, you are trying to execute your loop NumberOfClusters − 1 times; you would miss one element, so the fix is to start with zero index. I also improved your naming to meet Microsoft naming conventions. Loop variable is renamed because one-character names are bad (how would you do search, for example?); ++index provides better performance then index++ without change in results. (It looks strange, but try to test it.) Return value is added to your method, otherwise creation of objects would be pointless and eventually would cause destruction of them by the Garbage Collector (http://en.wikipedia.org/wiki/Garbage_collector_%28computing%29[^]).

—SA