This exam tips covers Exam Tips within Input Validation for GCSE Computer Science. Revise Input Validation in 3.2 Programming for GCSE Computer Science with 15 exam-style questions and 8 flashcards. This topic shows up very often in GCSE exams, so students should be able to explain it clearly, not just recognise the term. It is section 5 of 6 in this topic. Treat this as a marking guide for what examiners are looking for, not just a fact list.
Exam Tips
- Validation ≠ Verification: Validation checks data is sensible; verification checks it's what user intended (e.g., enter twice)
- Doesn't prove accuracy: Data can be valid but wrong (fake name passes validation)
- Combine checks: Often need multiple validation types for one field
Practice questions for Input Validation
A program asks the user to enter a score between 1 and 10. Which validation check should be used to ensure the number is within this range?
A registration form collects a username. The username must: not be blank, contain only letters and numbers, and be between 6 and 20 characters long. Identify three validation checks and explain what each one does for this input.