import csv
with open('v.csv', 'w') as csvfile:
cwriter = csv.writer(csvfile, delimiter=' ', quotechar='|', quoting=csv.QUOTE_MINIMAL)
for w, c in p.items():
cwriter.writerow(w + c)
Here, p
is a dictionary, w
and c
both are strings.
When I try to write to the file it reports the error:
ValueError: I/O operation on closed file.
Indent correctly; your for
statement should be inside the with
block:
import csv
with open('v.csv', 'w') as csvfile:
cwriter = csv.writer(csvfile, delimiter=' ', quotechar='|', quoting=csv.QUOTE_MINIMAL)
for w, c in p.items():
cwriter.writerow(w + c)
Outside the with
block, the file is closed.
>>> with open('/tmp/1', 'w') as f:
... print(f.closed)
...
False
>>> print(f.closed)
True
file = open("filename.txt", newline='')
for row in self.data:
print(row)
Save data to a variable(file
), so you need a with
.
I had this problem when I was using an undefined variable inside the with open(...) as f:
.
I removed (or I defined outside) the undefined variable and the problem disappeared.
Same error can raise by mixing: tabs + spaces.
with open('/foo', 'w') as f:
(spaces OR tab) print f <-- success
(spaces AND tab) print f <-- fail
I was getting this exception when debugging in PyCharm, given that no breakpoint was being hit. To prevent it, I added a breakpoint just after the with
block, and then it stopped happening.
Source: Stackoverflow.com