Producing Robust Programs

Producing Robust Programs

1. Sanitisation

2. Validation

   • Checking input data is sensible and in the right format
   • Length check - the input must not be too long or too short.
   • Format check - the data must be in the correct format, such as entering a date in the format DD/MM/YYYY.
   • Range check - the input must fall within a specified range. This is usually applied to numbers and dates, but can apply to characters.
   • Presence check - a data value must be entered. For example, entering a quantity when placing an order.

3. Authentication

4. Maintainablility

   • The process of ensuring that a program is easy to understand, modify and update.