Nowhere do you mention use of a debugger. Are you using one?
You can't write programs if you're not prepared to debug them on your own. It sounds like you took some code, compiled it, and hoped for the best, and if something goes wrong, throw together arbitrary bits of code to see if the problem goes away.
Instead, you should have prepared for the inevitable step of having to debug the program at some point, whether that point is now or in the future.
actually I am building the code step by step (on my own!)and it was working properly for all the previous steps, but now I encounter this problem since few days and I have no clue about how to solve it. I tried all the ways I am familiar with. but i am a student and trying to learn.
many thanks for your time
Last edited by Yohanna; September 27th, 2010 at 01:39 PM.