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Question

I am trying to create a very basic scoreboard system. Scores to be read into a list from a file. If name exists the list to be updated with further scores (append). New line to be created if name does not exist. I think its the append new score to list that's not working. Any help appreciated - learning.

message=""

#ask for name and score
name = input("Please enter the name you wish to add")
score = input("Please enter the high score")

#open the highscores line and read in all the lines to a list called ScoresList.
#  Then close the file.
scoresFile = open("highscores.txt","r")
ScoresList = scoresFile.readlines()
scoresFile.close()

#for each line in the ScoresList list
for i in range(0, len(ScoresList) ):

    #check to see if the name is in the line
    if name in ScoresList[i]:

        #append new score to list
        tempscore= ScoresList[i]
        ScoresList[i]=tempscore.append(score)
        message="Updated"

        #write the scores back to the file. Overwrite with the new list
        scoresFile = open("highscores.txt","w")
        for line in ScoresList:
            scoresFile.write(line + "\n")
        scoresFile.close()

    else:
       message = "Not updated"

if message=="":
        scoresFile = open("highscores.txt","a")
        scoresFile.write(name + str(score)+"\n")
        scoresFile.close()

Answer 1

ScoresList[i]=tempscore.append(score) makes ScoresList[i] equal to None as append is an in place method. So you are storing all None's in your ScoresList .

If you want to add a score to the name:

name = input("Enter your name").rstrip() # make "foo" == "foo "
score = input("Enter your score")
with open("highscores.txt","a+") as f: # a+ will allow us to read and will also create the file if it does not exist
    scores_list = f.readlines()
     # if scores_list is empty this is our first run
    if not scores_list:
        f.write("{} {}\n".format(name, score))
    else:
        # else check for name and update score
        new_names = []
        for ind, line in enumerate(scores_list):
            # if name exists update name and score
            if name in line.split():
                scores_list[ind] = "{} {}\n".format(name, score)
                break # break so we don't add existing name to new names
        else:
            # else store new name and score
            new_names.append("{} {}\n".format(name, score))


        # all scores updated so open and overwrite
        with open("highscores.txt","w") as scores_file:
             scores_file.writelines(scores_list + new_names)

You also you already have all the scores in a list so open the file just once outside the loop when ScoresList is updated and overwrite instead of repeatedly opening each time.

If you want to add new scores instead of overwriting the score add score to the line instead of the name:

scores_list[ind] = "{} {}\n".format(line.rstrip(), score)

If you want to separate by commas and append each new score to exisiting names:

with open("highscores.txt","a+") as f: # a+ will allow us to read and will also create the file if it does not exist
    scores_list = f.readlines()
     # if scores_list is empty this is our first run
    if not scores_list:
        f.write("{},{}\n".format(name, score))
    else:
        # else check for name and update score
        new_names = []
        for ind, line in enumerate(scores_list):
            # if name exists update name and score
            if name.rstrip() in line.split(","):
                scores_list[ind] = "{},{}\n".format(line.rstrip(), score)
                break # break so we don't add existing name to new names
        else:
            # else store new name and score
            new_names.append("{},{}\n".format(name, score))


        # all scores updated so open and overwrite
        with open("highscores.txt","w") as scores_file:
             scores_file.writelines(scores_list + new_names)