Does anyone have any example code for integrating with WorldPay using MVC3? Specifically posting the XML order to WorldPay. I have googled all the way but couldnt find the relevant information .
WorldPay uses a pretty simple REST API. Their developer documentation, which I think contains C# examples, should be all you need.
MVC doesn't change how you'd interact with them. The code would be the same with a Silverlight or Windows Forms application.