Week 5 - Validation and Reliable Input

This week focuses on reliable user input. The coding task uses validation methods, while the theory work draws on Section 4 ideas about selection, iteration and validation order.

Key knowledge and skills

• existence, type and range checks
• repeated input using loops until valid data is entered
• methods that isolate validation logic
• designing software that rejects invalid data safely
• explaining why validation improves reliability but does not guarantee truth

Coding principles covered

• validate data before using it in calculations
• check existence, then type, then range
• use TryParse instead of risky direct conversion
• keep validation logic reusable rather than rewriting it for each field

Useful theory pages

• Section 4: a. What You Need To Know

Task checklist

• [ ] Open the Week 5 programming task outline and complete the Week5_Validation console app module.
• [ ] Use TryParse and range checks so the program keeps asking until valid input is entered.
• [ ] Complete Section 4 Test Your Knowledge.
• [ ] Complete Section 4 Applied Task.
• [ ] Upload your validation program and your Section 4 responses to your GitHub repo.