相关paypal express check支付功能集成的资料
快速结帐 Express Checkout产品演示demo
https://www.paypal-biz.com/demo/index.php?cmd=001AMUI3K3B3NKN
Paypal Integration Wizard
https://www.paypal-labs.com/integrationwizard/ecpaypal/intro.php#
PayPal测试环境(Sandbox)使用指南
https://www.paypal-biz.com/development/documentation/PayPal_Sandbox_Guide_CN_V2.0.pdf
Express Checkout API Getting Started Guide
https://www.x.com/developers/paypal/documentation-tools/quick-start-guides/express-checkout-api
SDK Index
New PayPal SDKs (看完以上简单流程介绍后可下载相应版本的demo了解其运行过程)
https://www.x.com/developers/paypal/documentation-tools/paypal-sdk-index#NVP
Getting Started With Express Checkout
https://cms.paypal.com/us/cgi-bin/?cmd=render-content&contentID=developer/ehowtoapiECGettingStarted
PayPal Express Checkout 實作手記
http://mobile.dotblogs.com.tw/suehilary/archive/2011/10/20/44568.aspx
Paypal快速支付接口参数的含义(大多数参数仍支持但不推荐使用，api文档由具体的推荐使用的参数)
