String Manipulation

Learning Objectives

In this post we will focus on string manipulation techniques using five common techniques used in most procedural programming languages:

• LEFT: to extract characters at the beginning of a string,


• RIGHT: to extract characters at the end of a string,


• LENGTH: to find out the number of characters in a string,


• MID: to extract a set number of characters at a given position in a string,


• LOCATE: to find if a substring is included in another string and if so return the position of this substring in the string.

Your Challenge

Check the code below which is based on the 5 string manipulation functions we mentioned above: Left, Right, Length, Mid, and Locate.

Your challenge is to tweak this code to ask the user to enter their school username in the following format:

• Year Group Using two digits (e.g. “07” for year 7, “11” for year 11, “00” for staff members)
• 1 character for their initial (first letter of their firstname)
• The user’s lastname
• A 2-digit code: “_S” for students, “_T” for teachers, “_A” for admin staff.

For instance the following usernames are valid usernames:

07jFox_S
09kJohnson_S
11rTaylor_S
00pJones_T
00jOliver_A

Your program should read the username and decide:

• If the username is less than 6 characters long the program should ask the user to enter a valid username.
• If the username does not contain the character “_” it should also ask the user to enter a valid username.
• If the username is valid, the program should decide if the user is a member of staff or a student.
• If they are a student the programme should find out their year group.
• The program should also display the initial of the student as well as their lastame.
• Finally the program should display whether the user is a Student, a Teacher or an Admin member of staff.