Hey everybody. I'm new to the forum and have some experience with C#. I need to build a 2D box on screen using C# and have a ball that bounces around inside the box. I have to make a command key to stop and start the ball. I'm pretty lost here and don't even know where to start. Any advice would be helpful.

What do you mean by bounce? The simplest form of making a ball bounce would be to invert the x or y speed each time it hits an edge (x for vertical collision, y for horizontal). For example:

Ball moving at 2 x pixels per tick and 5 y pixels per tick hits the bottom of the box (down and to the right), this bounces and is now 2 x pixels per tick and -5 y pixels per tick (up and to the right). Then it hits the right boundary and becomes -2, -5 (up and left).

This, of course, is not very realistic unless the environment is intended to be frictionless and free of gravity. I'll upload an old project I did that is pretty similar to this (only it incorporates gravity, friction, momentum, and elasticity as well and supports dragging the objects with a mouse, resizing selected shapes with the mouse wheel, and smashing them into eachother).

@skatamatic could not unzip or open your zip map. Using Windows 7 Home premium.

@skatamatic could not unzip or open your zip map. Using Windows 7 Home premium.

Try renaming it to .Rar and using WinRAR. This site wouldn't let me upload a .rar file so I just changed the extension and hope for the best :'(

Haha and maybe it's for the best that you can't - your math is likely superior to mine and you will probably find a lot of things that are wrong with it!

Update: I tried downloading it at work and have the same problem. I will re-upload it when I get the chance.