When you asked this question yesterday:
How to integrate paypal SDK to windows application ?[
^] you were told what to do. That advice has not changed.
Except I would add this: Never, ever, accept code from a insecure website to handle anything to do with real money.
You do not know who is giving you the code, you do not know what it does, you do not know that it places the monies correctly into the appropriate account, without passing the details to any third parties.
Only get such code from reputable card transaction service companies - the scope for fraud otherwise is far too large. And remember, you personally could be liable for any monies lost if your action is seen to be negligent - which getting your code from a public forum would most certainly be!
If you do not know what you are doing in good detail, then you are setting yourself up to fail, in ways that could easily end up with you being fined or jailed for financial fraud. Learn what you are doing, don't assume that a "random website" full of strangers is the best way to get your work done, particularly when real money is involved!
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