Programs using files

0_Session6.py

'''
program to read from a file using read() and write to another file using write()
'''
with open("input.txt","r") as reader:
    lines = reader.read()

with open("output.txt","w") as writer:
    writer.write(lines)

readlines.py

'''
Using readlines() to read the contents of the file. It reads the contents of the file and returns a list of lines.
strip('\n') is used to strip the newline character from the end of the string
'''
with open("input.txt") as reader:
    lines = reader.readlines()
    for x in lines:
        print(x.strip('\n'))

todolist_v1.py

'''
The todolist version using a list variable
'''

def add_item():
    item = input("Enter the new item:")
    todolist.append(item)

def remove_item():
    item = input("Enter the item to be removed: ")
    todolist.remove(item)

todolist = []
while True:
    print("Press\n 1 to add item \n 2 to remove item \n 3 to exit")
    choice = int(input())
    if choice == 1:
        add_item()
    elif choice == 2:
        remove_item()
    else:
        break
print(todolist)

todolist_v2.py

'''
Todolist using files for storage
'''

def read_file():
    tasks = []
    with open("task.txt", "r") as reader:
        lines = reader.readlines()
        for line in lines:
            tasks.append(line.strip('\n'))
    return tasks


def write_file(tasks):
    with open("task.txt", "w") as writer:
        for line in tasks:
            writer.write(line + "\n")


def add_item():
    item = input("Enter the new item:")
    todolist.append(item)


def remove_item():
    item = input("Enter the item to be removed: ")
    todolist.remove(item)


todolist = read_file()
print(todolist)
while True:
    print("Press\n 1 to add item \n 2 to remove item \n 3 to exit")
    choice = int(input())
    if choice == 1:
        add_item()
    elif choice == 2:
        remove_item()
    else:
        break
print(todolist)
write_file(todolist)