codeigniter paypal integration

I am building an web application which had list of items, and once the user is fully registered, he can show his interest in particular item. To book that item he needs to pay $1 through paypal. I have all sandbox settings with me. Now what should be there in payment page form, and which library is suitable for this? I开发者_运维问答 am absolutely clueless as to how paypal actually works.

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Check out the following links:

PayPal Library for Codeigniter

This is a library built specifically for Codeigniter

http://codeigniter.com/wiki/PayPal_Lib/

PayPal's API + Site Integration Page

This includes code examples and an API library for PHP

https://cms.paypal.com/us/cgi-bin/?cmd=_render-content&content_ID=developer/library_download_sdks

PayPal's Developer Site

Yes it really is their developer site (check the certificate)

https://www.x.com/index.jspa