How to replace text in a txt file with python?

Question

I'm trying to replace text in a .txt file using a .py script. Here's what i have so far:

docname=raw_input("Enter a document name: ")    
fo=open(docname, 'r+')    
string=fo.read()    
replace=raw_input("Enter what you want to replace: ")    
replacewith=raw_input("Enter what you want to replace it with: ")    
out=string.replace(replace,replacewith)    
fo.write(out);    
fo.close()    
print "Check the document!"    
closeInput = raw_input("Press ENTER to exit")

I have a txt file called "test.txt" (in the same directory as the .py script). When I enter "test.txt", it asks what I want to replace, as expected. When I fill out that, it asks for what I want to replace it with.

I fill out that, and the program closes. No "Check the document!" or anything. And worst of all, it doesn't replace it with the second string.

Please help!

Domysee · Accepted Answer · 2013-12-28 23:36:36Z

1

you have 2 possibilities:

if you want to open the file just once, you should reset the position of the stream with fo.seek(0)
you can close and reopen the file with fo = open(docname, 'w')

The first option has one problem: if the replace-text is shorter than the original-text, some text will be left over at the end. To illustrate what I'm talking of: You have the text '12345' and want to replace '12' with 'a', then the resulting file would contain 'a3455'

answered Dec 28, 2013 at 23:36

Domysee

12.9k10 gold badges55 silver badges85 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

How to replace text in a txt file with python?

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related