Python 将字符串添加到文件中的每一行
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时间：2020-08-18 20:04:04 来源:igfitidea点击:
Python Add string to each line in a file
提问by Pcntl
I need to open a text file and then add a string to the end of each line.
我需要打开一个文本文件，然后在每行的末尾添加一个字符串。
So far:
迄今为止：
appendlist = open(sys.argv[1], "r").read()
回答by Guy Gavriely
s = '123'
with open('out', 'w') as out_file:
with open('in', 'r') as in_file:
for line in in_file:
out_file.write(line.rstrip('\n') + s + '\n')
回答by Tim Wilder
def add_str_to_lines(f_name, str_to_add):
with open(f_name, "r") as f:
lines = f.readlines()
for index, line in enumerate(lines):
lines[index] = line.strip() + str_to_add + "\n"
with open(f_name, "w") as f:
for line in lines:
f.write(line)
if __name__ == "__main__":
str_to_add = " foo"
f_name = "test"
add_str_to_lines(f_name=f_name, str_to_add=str_to_add)
with open(f_name, "r") as f:
print(f.read())
回答by José Tomás Tocino
Remember, using the +operator to compose strings is slow. Join lists instead.
请记住，使用+运算符组合字符串很慢。改为加入列表。
file_name = "testlorem"
string_to_add = "added"
with open(file_name, 'r') as f:
file_lines = [''.join([x.strip(), string_to_add, '\n']) for x in f.readlines()]
with open(file_name, 'w') as f:
f.writelines(file_lines)
