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I am new to C# and not up to speed with OOP.

I am converting a TurboC program to Windows.

The old program used a global variable to store user key srokes.
The C# prog has a static variable for the same purpose.
This is updated by an overriden OnKeyDown.

However on entering a method, called via a form menu, key strokes are ignored.

I fear it is something fundamental in my approach.
Suspect not grasping change from procedural programming.

Can anyone point me in the right direction.

Thanks
Posted
Comments
OriginalGriff 27-Oct-10 7:46am
   
What are you doing in your method? Are you looping and waiting for the static variable to change?
Because if you are, it won't.
Toli Cuturicu 27-Oct-10 9:14am
   
Fake answer by OP converted to this comment:
Thank you OriginalGriff.
I am and it isn't.
Solution or guidance?
Thanks
Keith Barrow 27-Oct-10 9:16am
   
He's kinda given you the answer, the loop is blocking the keystrokes. It'd be better raise an event when you update the static variable.

1 solution

I think you need to set the KeyPreview property to True to get all keystrokes.

http://msdn.microsoft.com/en-us/library/system.windows.forms.form.aspx[^]

If you mean that your method executes for quite some time, then this means that the message loop that deals with application messages (like a keystroke) isn't handled. If it would take to long, you would also get the "(not responding)" in the taskmanager.

You could execute your method in a thread. The most basic way to do this is:
using System.Threading;
// ...
new Thread (new ThreadStart (SomeObject.SomeMethod)).Start();


The code above doesn't maintain a reference to the thread, but it's just a simple example.

Here is some extra reference:
http://www.yoda.arachsys.com/csharp/threads/[^]

http://www.yoda.arachsys.com/csharp/threadstart.html[^]

It is also important to know that Invoke must be used if you would like to do some screen updating from a thread:
http://msdn.microsoft.com/en-us/library/zyzhdc6b.aspx[^]

Some info on how to control the thread:
http://msdn.microsoft.com/en-us/library/7a2f3ay4%28VS.80%29.aspx[^]

You could also do without threads and bloat your methods with an excessive amount of Application.DoEvents(); to ensure the message loop is handled. This is however quite dangerous and error prone. Every save person will advise against the use of this hack... so, be warned!

Good luck!
   

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