Python - csv文件在使用csv writer后为空 [英] Python - csv file is empty after using csv writer

问题描述

这里是Python新手。我试图解决在一个更大的程序中编写csv文件的问题，并决定回到基础来尝试找到问题。

我运行了一个确切的代码示例来自Python csv读写文档：

  import csv 
 spamWriter = csv.writer .csv'，'w'），delimiter =''，quotechar ='|'）
 spamWriter.writerow（['Spam'] * 5 + ['Baked Beans']）
 spamWriter.writerow （['Spam'，'Lovely Spam'，'Wonderful Spam']）
  

我的工作目录并点击eggs.csv文件为空，报告为0 kb。同样的事情发生在我的较大的程序（空csv文件）。

编辑：

br>
我刚刚尝试将代码修改为：

  import csv 
 csvOut = open .csv，wb）
 spamWriter = csv.writer（csvOut，delimiter =''，quotechar ='|'）
 spamWriter.writerow（['Spam'] * 5 + [' Beans']）
 spamWriter.writerow（['Spam'，'Lovely Spam'，'Wonderful Spam']）
 csvOut.close（）
  pre> 
 
 
这个工作。我不知道为什么第一个不适合我。
解决方案
我不太熟悉 csv 模块，但这看起来像一个文件IO问题比一个 csv 问题。 
 
 
 
在文件中看不到任何内容的原因是python仍然打开了该文件。 
 
 
 
因此，不要这样做：
  spamWriter = csv.writer（open（'eggs.csv'，'w'），delimiter =''，quotechar ='|'）
  
这样做：
  f = open（'eggs.csv'，'w '）
 spamWriter = csv.writer（f，delimiter =''，quotechar ='|'）
＃其余代码
 f.close（）
  
 
 
 
现在你应该在eggs.csv看到你想要的东西
 
 
 
 Hope这有助于
 
Python newbie here. I was trying to troubleshoot an issue with writing a csv file in a larger program and decided to go back to basics to try to find the problem.

I ran an exact code example from the Python csv reading and writing documention:
import csv     
spamWriter = csv.writer(open('eggs.csv', 'w'), delimiter=' ', quotechar='|')    
spamWriter.writerow(['Spam'] * 5 + ['Baked Beans'])
spamWriter.writerow(['Spam', 'Lovely Spam', 'Wonderful Spam'])
When I go to my working directory and click on "eggs.csv" the file is empty is reported as being "0 kb".  This same thing was happening in my larger program (empty csv files).  Am I missing something completely obvious?

Thank you!

EDIT:

I just tried modified the code to:
import csv
csvOut=open("eggs.csv", "wb")
spamWriter = csv.writer(csvOut, delimiter=' ', quotechar='|')
spamWriter.writerow(['Spam'] * 5 + ['Baked Beans'])
spamWriter.writerow(['Spam', 'Lovely Spam', 'Wonderful Spam'])
csvOut.close()
And this worked.  I am not sure why the first doesn't work for me.
解决方案
I'm not too familiar with the csv module, but this does look like a file IO problem more than a csv problem. 

The reason that you see nothing in the file is that python still has the file open. You need to close it.

So rather than doing this:
spamWriter = csv.writer(open('eggs.csv', 'w'), delimiter=' ', quotechar='|')
Do this instead:
f = open('eggs.csv', 'w')
spamWriter = csv.writer(f, delimiter=' ', quotechar='|')
# the rest of your code
f.close()
Now you should see what you want in eggs.csv

Hope this helps

                        
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