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Changing stored scores with certain username in a txt file. Python

I just started my gcse computer science course where we learn python. I need help with updating a user's score to a certain account. I am storing usernames passwords and scores in a text file and need to know how to change a score from a certain account. My text file is set out like this:
Bobby,pass,98
Pip,Noob,19
pog,man,1234
E.g Bobby is the username and pass is the password and 98 is the score so what I need is a way to scan for that certain username and change the score (98).
The code that I use for creating an account and logging in is this:
def SignUp():
print("""Please enter a username and password.""")
newUsername = input("Your username: ")
#Now askes for a password
print("""Cool now enter a password
""")
newPassword = input("Your Password: ")
print("Nice.")
newscore = input("Now give me a score")
#Puts the username and password into a txt
file = open("Login.txt","a")
file.write("""
""")
file.write (newUsername)
file.write (",")
file.write (newPassword)
file.write (",")
file.write (newscore)
file.close()
def Login():
userLogin = input("Please enter your username. ")
userPass = input("Password: ")
logged_in = False
with open('Login.txt', 'r') as file:
for line in file:
username, password, score = line.split(',')
if username == userLogin:
# Check the username against the one supplied
logged_in = password == userPass
print(str(score))
print("you logged in")
break
SignUp()
Login()
I'm quite new to python as you can probably tell so any help will be appreciated.

The easiest way is to read the entire file, then rewrite the entire thing with the changed number. This is only practical with small files:
def changeScore(username, newScore):
file = open("Login.txt", "r")
lines = file.readlines()
file.close()
file = open("Login.txt", "w")
for line in lines:
data = line.split(",")
if data[0] == username:
data[2] = str(newScore) + "\n"
file.write(",".join(data))
else:
file.write(line)
file.close()

One way to do this is to find the line you want by the provided userName, and then change the line. You can just re-write all the lines back into the txt file.
def changeScore(userLogin, newScore):
with open('Login.txt', 'r') as file:
lines = file.readlines()
for line in lines:
if line.startswith(userLogin):
username, password, score = line.split(",")
line = f"{username},{password},{newScore}\n"
with open('Login.txt', 'w') as file:
file.write("".join(lines))

how can i make store a username in txt file without having the same username twice?

user = input("\nInput user's Login ID: ")
while True:
password = str(input ("Input user's Password: "))
rpass = str(input("Re-enter the Password: "))
if password == rpass:
file = open("username.txt", "a")
file.write (user)
file.close()
break
else:
print("You have entered the wrong password, Try Again")
I want make a program where users can sign up with their username and password and it can be stored into a txt file. And the next person that is going to sign up won't be able to use the same username.
I renewed the code but the same problem happened, the previous username is not detected.

Every time you write to the file, it appends to the same line.
if data == user+ ":" +password:
This condition is never true as a result.
One possible solution is to add \n after every write.
file.write (user +" : "+ password +"\n")
And your condition would be
if data == user+ " : " +password:
Be mindful of whitespaces and other characters. It should be an exact match with this method.
Edit: You're checking whether the new username and password together are a match.
What you should be doing is matching user with data.split(':')[0][:-1] -
if data.split(":")[0][:-1] == user
This will collect the string till the ':' and truncate the trailing space.

If you want to use the parse module, you can run pip install parse and use this code:
import parse
pattern = '{[a-z][A_Z][0-9]} : {[a-z][A_Z][0-9]}'
lines = []
user = input ("enter username: ")
password = input ("enter password: ")
with open('username.txt', 'r') as f:
line = f.readline()
while line:
u, p = parse.parse(pattern, line)
lines.append((u, p))
line = f.readline()
users = [ u for (u, p) in lines ]
if user in users:
print(f'Username {user} is taken, please try again.')
else:
with open('username.txt', 'a') as f:
f.write(f'{user} : {password}')
print(f'Username and password successfully created.')

How to read external file in python?

i need to be able to save and get usernames and passwords from an external file. this is what i have done so far however it constantly says that username or password is incorrect even when i enter it correctly. does anyone know how to fix this problem.
this is my current code
import time
print("Welcome...")
welcome = input("Do you have an acount? y/n: ")
if welcome == "n":
while True:
username = input("Enter a username:")
password = input("Enter a password:")
password1 = input("Confirm password:")
if password == password1:
file = open("gcsetask.txt", "a")
file.write(username + ":" + password)
file.write('\n')
file.close()
welcome = "y"
time.sleep(0.4)
print("now lets login")
break
print("Passwords do NOT match!")
if welcome == "y":
while True:
login1 = input("Enter username:")
login2 = input("Enter Password:")
file = open("gcsetask.txt", "r")
data = file.readlines()
file.close()
if data == (login1 + ":" + login2):
print("Welcome")
break
print("Incorrect username or password.")

Three methods to read a file
read() It returns the read bytes in form of a string.
fileObject.read()
You can also define, how many bytes to read by
`fileObject.read([n]) //If n is not define, it will read the whole file`
readline([n]) It reads the line and return in the form of string, It only read single line
fileObject.readline([n])
readlines() It reads all the lines of the file and return each line a string element in a list
fileObject.readlines()
Hope it helps

I have changed the code to look at each line of that file. Allowing multiple users.
import time
print("Welcome...")
welcome = input("Do you have an acount? y/n: ")
if welcome == "n":
while True:
username = input("Enter a username:")
password = input("Enter a password:")
password1 = input("Confirm password:")
if password == password1:
file = open("gcsetask.txt", "a")
file.write(username+":"+password)
file.write('\n')
file.close()
welcome = "y"
time.sleep(0.4)
print("now lets login")
break
print("Passwords do NOT match!")
if welcome == "y":
while True:
login1 = input("Enter username:")
login2 = input("Enter Password:")
file = open("gcsetask.txt", "r")
data = file.readlines()
file.close()
for line in data:
if line == (login1+":"+login2+"\n"):
print("Welcome")
break
else:
print("Incorrect username or password.")

The function readlines() saves each line in a string inside a list.
If a file contains-
first line
second line
readlines() gives: ['first line','second line']
Try accessing them using index such as data[0] and data[1]

When you use file.readlines(), the function returns a list of all lines in the file. Thus, when you define data as:
data = file.readlines()
if you print(data), you get something similar to:
['user:pass\n'] # note the the \n at the end
Then, in the following line:
if data == (login1+":"+login2):
you're trying to compare a string (login1+":"+login2) with a list, which is always False because they have different type.
Changing the condition to:
if login1+":"+login2 in data:
should fix this problem (but you'll have a different one, see below).
About the trailing \n:
file.readlines() splits the lines in a list, but does not remove the newline character. This will cause your test to still fail always, because you don't account for it in the test.
Possible solutions are:
1) include the \n in the string you search:
if '{}:{}\n'.format(login1,login2) in data:
2) read the whole file and use splitlines instead, which will remove the newline characters
data = file.read().splitlines()

The readlines method returns the list of lines which you need to iterate on it to find the appropriate login information.
data = file.readlines()
login_info = f"{login1}:{login2}\n"
if login_info in data:
print("Welcome")
break
And also you can remove \n from the end of each line using splitlines.
data = file.read().splitlines()
login_info = f"{login1}:{login2}"
if login_info in data:
print("Welcome")
break
And another alternative is remove \n from parsed lines manually.
data = [line.rstrip('\n') for line in file.readlines()]
login_info = f"{login1}:{login2}"
if login_info in data:
print("Welcome")
break

How to use text file to load data and assign it to a variable?

i am new to python(learner).I created a simple program which asks for username and password and i used getpass()function to hide password
.But i want my program to load username and password from a text file.
#!/usr/bin/env python
import getpass
import os
print (' ')
print (' ')
print ('Please enter username and password in order to continue :')
print (' ')
print (' ')
user = (str(input(' USERNAME : ')))
usr_list = open("usr.txt", "r")
for line in usr_list:
line.strip()
if line == user:
password = getpass.getpass(" PASSWORD : ")
if password == 'root':
os.system("python3 cross.py")
else:
print ('WRONG! Password')
os.system("python3 sec.py")
else:
print ('WRONG! Username')
os.system("python3 sec.py")
now, if i remove text file and open function from code and insert a string like "user1" if user == "user1": it works fine.

You can read data from text file simple:
with open('your_text_file.txt', 'r') as f:
username = f.readline()
password = f.readline()
This is mean that you are open file "your_text_file.txt" for reading ('r' as second parameter) and we read first line, after that we read the next line
This is work if your username and password write in the different line:
your_text_file.txt:
sume_username
verylongandstrongpassword
You can read about read and write file here

Python read next line from what the user inputs

So basically I have a program which can create a users username and password in a document and search for the password used with the username that is input by the person using the program.
For example:
The programs asks me to input a username I enter: '13'.
Under 13 in the text document is 'sadfsdfsdf'.
I want the program to skip to below the 'Username: 13' and read and print 'Password: sadfsdfsdf'.
note that I have multiple usernames and passwords In the .txt file
u = 'Username: '
Thanks in advance!
def SearchRecordProgram():
while True:
user_search = input("Please enter the username you wish to see the password for: ")
full_user = u + user_search
if full_user in open('User_Details.txt').read():
print(" ")
print ("Username found in our records")
print(" ")
print(full_user)
break
else:
print("Username entered does not match our records")

So, imagining your file is like so:
Username : 13
Password : sadfsdfsdf
Username : 15
Password : Lalalala
You can parse it (with regular expressions) like so:
import re # regular expression module
regex = re.compile("Username :(.*)\nPassword :(.*)")
# read text from file
with open(filePath,'r') as f:
text = f.read()
u_pass = regex.findall(text)
# [(' 13', ' sadfsdfsdf'), (' 15', ' Lalalala')]
user_dict = {u:password for u,password in u_pass}
# {' 13': ' sadfsdfsdf', ' 15': ' Lalalala'}
Now you can get the password of someone by asking for the password of that user :
# given username and password_input
if username in user_dict and user_dict[username] == password_input:
# if username exists and password okay
print "Authentication succeeded."

When you want to open a file, you should almost always use the with statement:
with open('User_Details.txt') as read_file:
# Do reading etc. with `read_file` variable
This will ensure that any errors are being handled correctly and the file is not left open.
Now that the file is open, we need to loop through each line until we find one that matches our username. I hope you know how for loop works:
username = 'Username: 13' # Get this however you want
with open('User_Details.txt') as read_file:
for line in read_file:
line = line.strip() # Removes any unnecessary whitespace characters
if line == username:
# We found the user! Next line is password
And we need to get the next line which contains the password. There are many ways to get the next line, but one simple way is to use the next() function which simply gets us the next element from an iterable (the next line from a file in this case):
username = 'Username: 13'
with open('User_Details.txt') as read_file:
for line in read_file:
line = line.strip()
if line == username:
password = next(read_file)
break # Ends the for loop, no need to go through more lines
Now you have a password and an username, and you can do whatever you want with them. It's often a good idea to have the inputs and outputs outside of your program's logic, so don't print the password right inside the for loop, but instead just receive it there and then do the printing outside.
You might even wanna turn the whole search logic into a function:
def find_next_line(file_handle, line):
"""Finds the next line from a file."""
for l in file_handle:
l = l.strip()
if l == line:
return next(file_handle)
def main():
username = input("Please enter the username you wish to see the password for: ")
username = 'Username: ' + username
with open('User_Details.txt') as read_file:
password = find_next_line(read_file, username)
password = password[len('Password: '):]
print("Password '{0}' found for username '{1}'".format(password, username))
if __name__ == '__main__':
main()
Finally, it's absolutely insane to store anything in this format (not to mention password security stuff, but I get you're just learning stuff), why not do something like:
username:password
markus:MarkusIsHappy123
BOB:BOB'S PASSWORD
This could then easily be converted into a dict:
with open('User_Details.txt') as read_file:
user_details = dict(line.strip().split(':') for line in read_file)
And now to get a password for an username, you'd do:
username = input('Username: ')
if username in user_details:
print('Password:', user_details[username])
else:
print('Unknown user')

Maybe not the pretties, but something like this will work:
with open(users_file, "r") as f:
lines = f.read()
def get_password(user_id):
entries = iter(lines.splitlines())
for entry in entries:
if(entry.startswith("{}:{}".format(prefix, user_id))):
return next(entries)
print "Password:", get_password("13")

def SearchRecordProgram():
while True:
user_search = input("Please enter the username > ")
file = open('User_Details.txt')
usernames = file.readlines() # Read file into list
file.close()
if user_search in usernames: # Username exists
print ('Found Username')
password = usernames[usernames.index(user_search)+1]
print ('Password is: ' + password)
break # Exit loop
else: # Username doesn't exist
print("Username entered does not match our records")
Note that this will not work if a password happens to be a username, e.g:
user1
password1
user2
user3 # This is the password for user3
user3
password3
If you search for "user3" this code will output "user3" as the password for "user3" because it finds the first instance of "user3" (line 4) and then looks to the next line (line 5), which is the next username.
Even worse, if "user3" is the last line in the file, it will end with an error because there are no more lines. You could add a check that the index of the found username is even (i.e. index 0, 2, 4, 8) with this code:
if not usernames.index(user_search) % 2: # Checks the remainder after / by 2.
# If it's 0 then it's an even index.
password = usernames[usernames.index(user_search)+1]
print ('Password is: ' + password)
but there isn't much you can do if this happens.
However, you could manipulate the file of usernames to only have usernames like this:
lst = [0, 1, 2, 3, 4, 5, 6, 7]
print (lst[0::2])
which prints
[0, 2, 4, 6]
So the code could be changed to this:
def SearchRecordProgram():
while True:
user_search = input("Please enter the username > ")
usernames = open('User_Details.txt').readlines() # Read file into list
if user_search in usernames[0::2]: # Username exists
print ('Found Username')
password = usernames[1::2][usernames[0::2]].index(user_search)]
print ('Password is: ' + password)
break # Exit loop
else: # Username doesn't exist
print("Username entered does not match our records")
Here is a breakdown
password = usernames[1::2] # Gets the odd items (passwords)
[ # Get index item. The index returned from searching
# the usernames will be the same as the index needed
# for the password, as looking at just the odd items:
# [0, 2, 4, 6]
# [1, 3, 5, 7] - even has the same index as next odd.
usernames[0::2] # Gets even items (usernames)
].index(user_search)]
# Only searches the usernames. This
# means passwords being the same is not
# an issue - it doesn't search them