if I have a text file like:
StudentA:
10
20
30
40
StudentB:
60
70
80
90
I want to make a function :
def read_file(file,student):
file=file.open('file.txt','r')
when I call it,
read_file(file,StudentA)
it will show the list like:
[10,20,30,40]
How can I do it with a while loop?
I am not sure why you want to read using while, for-loop will do just fine. But here is a pythonic way to read files.
with open(...) as f:
for line in f:
<do something with line>
The with statement handles opening and closing the file, including if an exception is raised in the inner block. The for line in f treats the file object f as an iterable, which automatically uses buffered IO and memory management so you don't have to worry about large files.
while loop makes some sense. OP only wants to read part of the file. Rather than inserting a break into the for loop, you could do it with a while loop. (Although, both ways are a little messy)
break needs to be used. there is no getting away from that. But what most people miss when trying to read files is - what is that file is not present? what is that file is 1GB in size? these problems dont occur when one is at unit testing phase but when the code goes to the wild who knows what to expect.import re
def read_file(filename, student):
with open(filename, 'r') as thefile:
lines = [x.strip().upper() for x in thefile.readlines()]
if student[-1] != ':':
student += ':'
current_line = lines.index(student.upper()) + 1
output = []
while current_line < len(lines) and re.search('^\d+$', lines[current_line]):
output.append(int(lines[current_line]))
current_line += 1
return output
whileloop?