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What is StringIO in python used for in reality?

I am not a pro and I have been scratching my head over understanding what exactly StringIO is used for. I have been looking around the internet for some examples. However, almost all of the examples are very abstract. And they just show "how" to use it. But none of them show "why" and "in which circumstances" one should/will use it? Thanks in advance

p.s. not to be confused with this question on stackoverflow: StringIO Usage which compares string and StringIo.

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Hossein Avatar asked Nov 03 '11 14:11

Hossein


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2 Answers

It's used when you have some API that only takes files, but you need to use a string. For example, to compress a string using the gzip module in Python 2:

import gzip import StringIO  stringio = StringIO.StringIO() gzip_file = gzip.GzipFile(fileobj=stringio, mode='w') gzip_file.write('Hello World') gzip_file.close()  stringio.getvalue() 
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Petr Viktorin Avatar answered Oct 05 '22 23:10

Petr Viktorin


StringIO gives you file-like access to strings, so you can use an existing module that deals with a file and change almost nothing and make it work with strings.

For example, say you have a logger that writes things to a file and you want to instead send the log output over the network. You can read the file and write its contents to the network, or you can write the log to a StringIO object and ship it off to its network destination without touching the filesystem. StringIO makes it easy to do it the first way then switch to the second way.

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nmichaels Avatar answered Oct 05 '22 22:10

nmichaels