Input validation – checking that what is entered by the user is acceptable.
The following program checks that age is a positive number.
1. SEND “Please enter age” TO DISPLAY 3. RECEIVE age FROM (INTEGER) KEYBOARD 4. WHILE age < 0 DO 5. SEND “re-enter data” TO DISPLAY 6. RECEIVE age FROM (INTEGER) KEYBOARD 7. END WHILE
Note that acceptable does not mean accurate, just sensible.
Input validation is used in both National 5 and at Higher. It consists of 3 parts.
The use of the while construct allows the program to repeatedly ask the user to enter valid data.
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age=0 #Input Validation age=int(input('Please enter your age>')) while age<0 or age>120: # Check that age is between 0 and 120 print('Please check your age is between 0 and 120') age=int(input('Please enter your age>')) print('Welcome') |
This can also be used with strings, can you work out how to modify the code so that it would only take a ‘Yes’ ‘No’ answer?
