# Visual C# | Using lists exercise | Create a list containing the first 10 square numbers

This exercise is provided to allow potential course delegates to choose the correct Wise Owl Microsoft training course, and may not be reproduced in whole or in part in any format without the prior written consent of Wise Owl.

 Software ==> Visual C#  (79 exercises) Version ==> Any version of C# Topic ==> Using lists  (3 exercises) Level ==> Relatively easy Subject ==> C# training
Before you can do this exercise, you'll need to download and unzip this file (if you have any problems doing this, click here for help).

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To avoid having to draw the form needed for this exercise, right-click on the name of your project in Solution Explorer then choose Add --> Existing Item... (you can also press SHIFT + ALT + A to do the same thing).

Choose only the file called frmSquares.cs in the above folder to import it into your project, then edit Program.cs to make this the default form.

The aim of this exercise is to make the following work:

When you click on the button, your code should create a list containing the first 10 squares, then display the items in this list in the listbox.

Help follows for how to do this on the next page!

To get this code to work, start by creating a list.  Since the syntax is so hard to remember, here's a help:

How to create a list in C#.

As this shows, lists don't have to contain just bits of text: they can contain numbers, dates or anything else for that matter.

Now create a loop which goes from 1 to 10, adding the square of the number to the list for each iteration round the loop.

Finally, set the listbox's data source to be the list that you've created:

// show this list of squares

lstSquares.DataSource = squares;

That's it for this exercise!

You can unzip this file to see the answers to this exercise, although please remember this is for your personal use only.