python - 替换文本文件中的单词并将其写入python中的新文件

Question

所以我有一个包含以下内容的文本文件:

NUM,123
FRUIT
DRINK
FOOD,BACON
CAR
NUM,456
FRUIT
DRINK
FOOD,BURGER
CAR
NUM,789
FRUIT
DRINK
FOOD,SAUSAGE
CAR

我正在用“PIZZA”替换“BURGER”这个词

with open('input.txt','r') as f:
    data = f.readlines()
    for i, line in enumerate(data):
        if '456' in line:
            field = ','.join(data[i+3].split(',')[1])
            field = field.replace(field,'PIZZA')

如何将所有内容写回新文件，以便在新文件中包含:

NUM,123
FRUIT
DRINK
FOOD,BACON
CAR
NUM,456
FRUIT
DRINK
FOOD,PIZZA
CAR
NUM,789
FRUIT
DRINK
FOOD,SAUSAGE
CAR

谢谢!

Answer 1

你已经很接近了，请尝试以下操作:

with open('input.txt','r') as f:
    data = f.readlines()

with open('output.txt','w') as f:
    for i, line in enumerate(data):
        if '456' in line:
            fields = data[i+3].split(',')
            fields[-1] = 'PIZZA\n'
            data[i+3] = ','.join(fields)
        f.write(line)