Hướng dẫn write continue file python

I've been having trouble with this for a while. How do I open a file in python and continue writing to it but not overwriting what I had written before?

For instance:

The code below will write 'output is OK'. Then the next few lines will overwrite it and it will just be 'DONE'

But I want both 'output is OK' 'DONE' in the file

f = open['out.log', 'w+']
f.write['output is ']
# some work
s = 'OK.'
f.write[s]
f.write['\n']
f.flush[]
f.close[]
# some other work
f = open['out.log', 'w+']
f.write['done\n']
f.flush[]
f.close[]

I want to be able to freely open and write to it in intervals. Close it. Then repeat the process over and over.

Thanks for any help :D

asked Nov 16, 2012 at 7:54

user1431282user1431282

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Open the file in append mode. It will be created if it does not exist and it will be opened at its end for further writing if it does exist:

with open['out.log', 'a'] as f:
    f.write['output is ']
    # some work
    s = 'OK.'
    f.write[s]
    f.write['\n']

# some other work
with open['out.log', 'a'] as f:
    f.write['done\n']

answered Nov 16, 2012 at 7:57

0

Just pass 'a' as argument when you open the file to append content in it. See the doc

f = open['out.log', 'a']

answered Nov 16, 2012 at 7:57

Raunak AgarwalRaunak Agarwal

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You need to open the file in append mode the second time:

f = open['out.log', 'a']

because every time you open the file in the write mode, the contents of the file get wiped out.

answered Nov 16, 2012 at 7:58

codaddictcodaddict

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After the first writting, you need to use f = open['out.log', 'a'] to append the text to the content of your file.

answered Nov 16, 2012 at 7:58

with open["test.txt", "a"] as myfile:
    myfile.write["appended text"]

answered Nov 16, 2012 at 7:59

ymnymn

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How do you continue to write in a file in Python?

We can keep old content while using write in python by opening the file in append mode. To open a file in append mode, we can use either 'a' or 'a+' as the access mode. The definition of these access modes are as follows: Append Only ['a']: Open the file for writing.

How do you write to a file multiple times in Python?

write in multiple files python.

fn = open["path of input file.txt","r"].

fnew = fn. read[].

fs = fnew. split['\n'].

for value in fs:.

f = [open["path of output file to write.txt" %i,'w'] for i in range[len[list_of_files]]].

f. write[value].

f. close[].

How do you write to a file in Python?

Steps for writing to text files To write to a text file in Python, you follow these steps: First, open the text file for writing [or append] using the open[] function. Second, write to the text file using the write[] or writelines[] method. Third, close the file using the close[] method.

How do I save a file after writing in Python?

Saving a Text File in Python After learning about opening a File in Python, let's see the ways to save it. Opening a new file in write mode will create a file and after closing the file, the files get saved automatically.