Programming Excel with VBA and .NET

Determine Requirements

Requirements may be clearly laid out by your manager, or you may be completely responsible for determining them yourself. In either case, it is helpful to test assumptions at this point and get direct feedback from those who will use the product to make sure the requirements are realistic and that nothing was omitted.

It’s important to understand the difference between requirements and design: Requirements define what the product does; design determines how the product does it. In other words, it is a requirement that users log on before using the product, but determining how the username and password are validated is a design issue.

Requirements answer specific questions that help later with design, testing, and documentation. Table 6-2 categorizes some of the common questions.

Table 6-2. Common requirements questions

Category	Question
Function	What tasks does the product perform?
Audience	What level of experience do the users have with the tasks and with Excel in general?
Compatibility	What version or versions of Excel must the product work with?
	Do users have PCs, Macs, or both?
Deployment	Will the product be distributed on disk or from a network share or downloaded over the Internet?
Dependencies	Are there other components that must be installed for the product to work?
	Will this product be used by other products as a component?
	Does the product use external data, and if so what is the data source?

Obviously, these general questions ...