mmcclaf wrote:
On Feb 6, 3:09 pm, MRAB <goo...@mrabarnett.plus.com> wrote:
mmcclaf wrote:
On Feb 6, 10:25 am, Steve Holden <st...@holdenweb.com> wrote:
mmcclaf wrote:
Hi there,
I have to make a small database using cPickle. I'm having troubles
trying to read in the information if it's more than one line. I'm
pretty sure it's in the line "for line in stuff:" Can anyone help me
out? Basically the end result is wanting it to look something like
what is down below when list is typed in:
Last name First Name Email Address
Doe John
j...@doe.com
[code]
# @author: Ocdt Murray McClafferty 24656
# This will manage a small database using the cPickle module.
# It must maintain a list of last names, first names and email
addresses, and must let a user interact with the program
#
#!usr/bin/python
# -*- coding: utf-8 -*-
import sys
import cPickle
#
format = '%s %s %s'
try:
filename = sys.argv[1]
input = open(filename, 'r')
except IOError:
print 'File is not available, will create a new file now'
lastName='Last Name'
firstName='First Name'
email= 'Email'
#input.close()
output=open (filename, 'w')
total = format%(lastName, firstName, email)
cPickle.dump(total,output)
#cPickle.dump(firstName,output)
#cPickle.dump(email,output)
output.close()
except EOFError:
print 'File is empty'
#datas = cPickle.load(input)
while True:
command=sys.stdin.readline()[:-1]
if command=='list': #lists the data in the file
input = open(filename, 'r')
stuff=cPickle.load(input)
for line in stuff:
#firstName=cPickle.load(input)
#email=cPickle.load(input)
#print repr (lastName).rjust(10), repr(firstName).rjust(20),
repr
(email).rjust(20)
stuff=cPickle.load(input)
print stuff
print line
input.close()
if command=='exit' or command=='quit' : #NEVER forget the exit!!!
print 'Save changes? y for Yes, n for No'
commandSave=sys.stdin.readline()[:-1]
if commandSave =='y': #if the user wants to save
output=open(filename, 'w')
cPickle.dump(work,output)
output.close()
sys.exit(0)
if commandSave =='n': #no save
input.close()
sys.exit(0)
if command=='add': #adds an entity to the file
print 'Last name?'
lastName=sys.stdin.readline()[:-1]
print 'First name?'
firstName=sys.stdin.readline()[:-1]
print 'Email address?'
email=sys.stdin.readline()[:-1]
work = format%(lastName, firstName, email)
#output=open(filename, 'w')
#data=cPickle.load(output)
#data.append(work)
#output.close()
output=open(filename, 'a')
cPickle.dump(work,output)
output.close()
[/code]
All help would be appreciated. I am new to Python and this seems to be
quite a challenge for me.
Make sure you use modes "rb" and "wb" when you open the pickle files. If
you are running on Windows this can make a difference.
regards
Steve
--
Steve Holden +1 571 484 6266 +1 800 494 3119
Holden Web LLC http://www.holdenweb.com/
I've tried both rb and wb as well as r and w, there appears to be no
difference in the running of the code.
"cPickle.dump(work,output)" writes a string and
"stuff=cPickle.load(input)" just reads that string, so "for line in
stuff:" is iterating through the characters if the string. You need to
use cPickle.load() to read each string (line).
Ok, so I just modified that section to:
[code]
if command=='list': #lists the data in the file
input = open(filename, 'r')
stuff=cPickle.load(input)
for line in stuff:
You're still iterating over the string.
#firstName=cPickle.load(input)
#email=cPickle.load(input)
#print repr (lastName).rjust(10),
repr(firstName).rjust(20), repr
(email).rjust(20)
stuff=cPickle.load(input)
print stuff
input.close()
[/code]
And now it's printing it out ok, but then I get an EOFError at
stuff=cPickle.load(onput) at line 45.
You can just keep reading until EOFError occurs, at which point you know
you've reached the end of the file:
input = open(filename, 'rb')
try:
while True:
stuff = cPickle.load(input)
print stuff
except EOFError:
pass
input.close()
--
http://mail.python.org/mailman/listinfo/python-list
