File Handling (Cambridge (CIE) O Level Computer Science): Revision Note

Open

OPENFILE "fruit.txt" FOR READ

file = open("fruit.txt","r")

Close

CLOSEFILE "fruit.txt"

file.close()

Read line

READFILE "fruit.txt", LineOfText

file.readline()

Write line

OPENFILE "fruit.txt" FOR WRITE

WRITEFILE "fruit.txt", "Oranges"

file.write("Oranges")

Append a file

OPENFILE "fruit.txt" FOR APPEND

file = open("shopping.txt","a")

OPENFILE "employees.txt" FOR READ

endOfFile ← FALSE  // Set end of file flag to false

WHILE NOT endOfFile DO
    READFILE "employees.txt", name  // Read line 1 (name)
    name ← TRIM(name)  // Remove extra spaces/newlines

    READFILE "employees.txt", department  // Read line 2 (department)
    department ← TRIM(department)  // Remove extra spaces/newlines

    READFILE "employees.txt", salary  // Read line 3 (salary)
    salary ← TRIM(salary)  // Remove extra spaces/newlines

    READFILE "employees.txt", age  // Read line 4 (age)
    age ← TRIM(age)  // Remove extra spaces/newlines

    IF name = "" THEN  // If name is empty (end of file)
        endOfFile ← TRUE  // Set end of file flag to true
    ELSE
        OUTPUT "Name: " & name  // Print name
        OUTPUT "Department: " & department  // Print department
        OUTPUT "Salary: " & salary  // Print salary
        OUTPUT "Age: " & age  // Print age
        OUTPUT ""  // Add a blank line for readability
    ENDIF
ENDWHILE

CLOSEFILE "employees.txt"

Greg
Sales
39000
43
Lucy
Human resources
26750
28
Jordan
Payroll
45000
31

# Open file in read mode
file = open("employees.txt", "r")

endOfFile = False  # Set end of file flag to false

while not endOfFile:  # While not end of file
    name = file.readline().strip()  # Read line 1 and remove extra spaces/newlines
    department = file.readline().strip()  # Read line 2
    salary = file.readline().strip()  # Read line 3
    age = file.readline().strip()  # Read line 4

    if name == "":  # If name is empty (end of file)
        endOfFile = True  # Set end of file flag to true
    else:
        print("Name: ", name)  # Print name
        print("Department: ", department)  # Print department
        print("Salary: ", salary)  # Print salary (fixed typo)
        print("Age: ", age)  # Print age
        print()  # Add a blank line for readability

# Close the file
file.close()

Greg
Sales
39000
43
Lucy
Human resources
26750
28
Jordan
Payroll
45000
31

OPENFILE "employees.txt" FOR APPEND

// Write employee details to the file
WRITEFILE "employees.txt", "Polly"  // Name
WRITEFILE "employees.txt", NEWLINE
WRITEFILE "employees.txt", "Sales"  // Department
WRITEFILE "employees.txt", NEWLINE
WRITEFILE "employees.txt", "26000"  // Salary
WRITEFILE "employees.txt", NEWLINE
WRITEFILE "employees.txt", "32"  // Age
WRITEFILE "employees.txt", NEWLINE

CLOSEFILE "employees.txt"

Greg
Sales
39000
43
Lucy
Human resources
26750
28
Jordan
Payroll
45000
31

Polly
Sales
26000
32

# Open file in append mode
file = open("employees.txt", "a")

# Write employee details to the file
file.write("Polly\n")        # Name
file.write("Sales\n")        # Department
file.write("26000\n")        # Salary
file.write("32\n")           # Age

# Close the file
file.close()

Greg
Sales
39000
43
Lucy
Human resources
26750
28
Jordan
Payroll
45000
31
Polly
Sales
26000
32