删除文本文件中的空格并就地覆盖

Question

How to check every line in a text file and remove white spaces at the beginning of each line?

Here is what I tried, but it gives me a blank file instead

with open("0.txt","r") as readfile, open("0.txt","w") as outfile:
    for line in readfile:
        if line.startswith(' '):
            outfile.write(line.replace(' ', '')) 

Answer 1

If you want to change file in-place I suggest using built-in module named fileinput .

import fileinput 
for line in fileinput.input("0.txt", inplace=True):
    print(line.lstrip(), end="")

Note that I specified empty end as these lines already have trailing newlines. If you want to know more about that module I suggest reading PyMOTW3 article .