我正在尝试将特定行添加到我的文件中的特定区域.我用这个:
new_file = open("file.txt", "r+")
for line in new_file:
if line == "; Include below":
line = line + "\nIncluded text"
new_file.write(line)
else:
new_file.write(line)
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但由于某种原因,我的内容file.txt是重复的.
编辑:如果我的文件看起来像:
blablablablablablabal
balablablabalablablbla
include below
blablablablablabalablab
ablablablabalbalablaba
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我想让它看起来像:
blablablablablablabal
balablablabalablablbla
include below
included text
blablablablablabalablab
ablablablabalbalablaba
Run Code Online (Sandbox Code Playgroud) 更多细节如下:
1st line
2nd line
3rd line
4th line
...
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现在想插入一个zero line之前命名的新行1st line.文件如下所示:
zero line
1st line
2nd line
3rd line
4th line
...
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我知道sed命令可以做这项工作,但如何使用python做到这一点?谢谢
我有这个 sample.csv 文件:
a 1 apple
b 2 banana
c 3 cranberry
d 4 durian
e 5 eggplant
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并有以下代码:
samplefile = open(sample.csv,'rb')
rows = samplefile .readlines()
outputfile = open(output.csv,'wb')
wr = csv.writer(outputfile)
for row in rows:
wr.writerow(row)
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我想要的是在 for 循环期间的某个时刻写入 outputfile 的第一行,即当 outputfile 可能已经有条目时。