IBillIt

IBillIt is a slightly powerful development framework.
IBillIt is built in C# under the .NET framework to work with .NET managed code, script, and native code.

Pick your language. We support it, including: Java, PHP, Visual Basic, C#, C, C , VBScript, JavaScript, Visual Basic.NET, VBA, VB6—and almost any other Windows development environment.

Accelerates development of your custom shopping cart for Authorize.net integration. The library includes special shopping-cart features, such as tracking of line items—so you don't have to build your own tracking system—the ability to total a variety of items (duty, taxes, line items), plus lots more.