使用 python 写入 csv 文件

Question

heres my little program. at the end i want to write the names and passwords into csv file like this:

Jack,9978
Sara,1647

but i cant?: my program output is correct but when i write it into csv it goes like:

Jack9978,Sara1674

how will you fix it?

import hashlib
import csv

answer = []
usr_pas = []

with open('...', 'r') as f:
    reader = csv.reader(f)
    for word in reader:
        usr_pas.append(word)

for i in range(999, 10000):
    num = str(i)
    m = hashlib.sha256()
    m.update(num.encode('utf-8'))
    hsh = m.hexdigest()
    hash_dict = {hsh: num}
    for key in list(hash_dict.items()):
        for value in usr_pas:
            if key[0] == value[1]:
                answer.append(value[0] +','+ key[1])

file = open("...", 'w', newline='')
with file:
    writer = csv.writer(file)
    writer.writerow(i.strip().replace(',', '') for i in answer)
file.close()

what did i wrong??

Answer 1

Try this (lines with comments are changed):

import hashlib
import csv

answer = []
usr_pas = []

with open('...', 'r') as f:
    reader = csv.reader(f)
    for word in reader:
        usr_pas.append(word)

for i in range(999, 10000):
    num = str(i)
    m = hashlib.sha256()
    m.update(num.encode('utf-8'))
    hsh = m.hexdigest()
    hash_dict = {hsh: num}
    for key in list(hash_dict.items()):
        for value in usr_pas:
            if key[0] == value[1]:
                answer.append(value[0] +','+ key[1] + '\n') #added '\n' at the end

file = open("...", 'w', newline='')
with file:
    writer = csv.writer(file)
    writer.writerow(i for i in answer) #removed i.replace
file.close()

Answer 2

I guess you want a csv file with multiple lines instead of one. If so, my suggestion is to use csv.csvwriter.writerows instead of csv.csvwriter.writerow . The latter is designed to write a single row. See the official document here . Indeed multiple lines might be created with \n manipulator, it means a single line with multiple elements that contains "new line", which seems awkward.

Since we can use the default delimiter (comma), we just need to manage each element in the line as a tuple (or a list). Answers should be added into list answer like this:

answer.append((value[0], key[1]))

while we write rows in this way:

writer.writerows(answer)

Let's put them together:

import hashlib
import csv 

answer = []
usr_pas = []

with open('...', 'r') as f:
    reader = csv.reader(f)
    for word in reader:
        usr_pas.append(word)

for i in range(999, 10000):
    num = str(i)
    m = hashlib.sha256()
    m.update(num.encode('utf-8'))
    hsh = m.hexdigest()
    hash_dict = {hsh: num}
    for key in list(hash_dict.items()):
        for value in usr_pas:
            if key[0] == value[1]:
                # answer.append(value[0] +','+ key[1])
                answer.append((value[0], key[1]))

file = open("...", 'w', newline='')
with file:
    writer = csv.writer(file)
    # writer.writerow(i.strip().replace(',', '') for i in answer)
    writer.writerows(answer)
file.close()