[Tutor] Replacing the string in a file

[Shashwat Anand]

You can try it by reading all data as string, replacing the string and then
write it to target file via opeing it in +w mode.

f = open('data.txt', 'rw').read().replace('Python', 'PYTHON')
f1 = open('data.txt',
'w')

f1.write(f)

HTH


On Fri, Jan 22, 2010 at 12:14 PM, vanam <raghavendra.gv.vanam at gmail.com>wrote:

> Hi all,
>
> I have been trying to write a script where in it has to replace a
> particular string in a file and write back to the file without intact
> of the contents
>
> I have tried below mentioned steps, but of no avail:
>
> 1. Created a file by name data.txt and included some text (For
> instance,
>
> ************************************************************************
> Then, I started searching for a good book on Python. I couldn't find
> any! I did find some O'Reilly books
> but they were either too expensive or were more like a reference
> manual than a guide. So, I settled for
> the documentation that came with Python. However, it was too brief and
> small. It did give a good idea
> about Python but was not complete. I managed with it since I had
> previous programming experience, but
> it was unsuitable for newbies.
> ************************************************************************
>
> 2.Read the file contents (For this opened the file in read mode -- log
> = open('data.txt','r')
>
> 3.Iterated through the text using for loop for reading the contents in
> the file -- for x in log:
>
> 4.Replaced the word  Python with PYTHON as indicated --- x  =
> x.replace('Python','PYTHON')
>
> 6.printed the full contents -- It had printed the full contents by
> replacing the word Python to PYTHON
>
> Python string did not get changed to PYTHON for the reasons that i did
> not open the file in write mode and written the string
>
> [Query]: How to write Python string to PYTHON to that file without
> intact of the full contents
>
> I was successful in routing the contents (with changed string to
> PYTHON) to a different file.
>
> And i am aware that opening the file in write mode will wipe out the
> previous contents.
>
> I have tried appending the content which it does but that is not my goal.
>
>
> 7. Closed the files outside for loop -- log.close()
> --
> Raghavendra  Vanam
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