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This program let you edit,save and load a list. This program also demonstrate how to use files, pickle (or cPickle), and built-in list method.

Python, 93 lines
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#!/usr/bin/python
# Filename : lister.py

import sys, pickle

global mylist
mylist = []

def takeinput():
	# take input from user to select which function
	try:	
		num = int(raw_input('--> '))
		if num == 1:
			printlist()
		elif num == 2:
			add()
		elif num == 3:
			delete()
		elif num == 4:
			save()
		elif num == 5:
			load()
		elif num == 6:
			quit()
		else:
			quit()
	except ValueError:
		quit()
	

def printlist():
	# print mylist
	print 'mylist is now:', mylist, '\n'

def add():
	# add an item to mylist
	s = str(raw_input('Enter the name of the object you want to add --> '))
	mylist.append(s) # add the 
	del s
	printlist()

def delete():
	# delete an item from mylist
	print # newline
	i = 0
	while i < len(mylist): 		  # use while loop to assign 'itm' to the  
		for itm in mylist:	  # items in the list. Then, print the number of  
			print itm,'is',i  # items and items in mylist.  
			i = i + 1	  # the numbers of the items and items is printed.
	
	print # newline
	s = int(raw_input('Enter the number of the object you want to delete --> '))
	del mylist[s] # delete the item using both 'del' function & indexing method
	del s	
	printlist()
	
def save():
	# save mylist
	mylist_data = 'lister.data' # The name of the file
	f =  file(mylist_data, 'w') # Open for 'w'riting
	pickle.dump(mylist, f) # dump/put the list into the file
	f.close()	       # close
	print 'Saved mylist :)'

def load():
	# load mylist
	mylist_data = 'lister.data'
	f = file(mylist_data)
	storedlist = pickle.load(f)
	print 'Loaded mylist :)'

def quit():
	# quit the program
	print 'Bye! :) \n'
	sys.exit()

# Script starts here
	
print '''\
Hi! this is a lister program.
Type:
1- print mylist
2- add an object to mylist
3- delete an object from mylist
4- save mylist
5- load mylist
6- quit\
'''

running = True

while running:
	takeinput() # Always take input from user until he/she quits the program

I write this program just to practice my Python skills to use list methods, files and pickle. It can be useful for someone whose want to learn using pickle and store list in your hard disk. Lastly, use it for fun :)

3 comments

Paul Courchene 16 years, 2 months ago  # | flag

This "lister module" I tried this module. It is neat. But, it will save a file (that contains strings for data), O.K. But when I try to reload the (saved) file I get an empty string back. If I look in the directory, such as c:\Python24 (Windows) I can find the saved file and open it with Notepad, and it is a fresh file with a date/time group that is new. However, this code will not reload the file, when attempting a reload, it says the string (file) is empty ????

nijtramsilenroctims 15 years, 7 months ago  # | flag

The Load function works!! The load function does work! The thing is the list isnt pased back to the rest of the program, so it disapears when the function returns. If the load function would end with something like:

return local_list_name

and be caled (in the event handling loop) with something as

global_list_name = Load()

then the list will be pased back to the main program

alternatively inside the Load function you can explicitly assign to the global variable(something like global.listname = ... but Im not sure)

Cheers

nijtramsilenroctims 15 years, 7 months ago  # | flag

sorry please remove. due to first needing to subscribe, and the break in the train of thought that causes I have inadvertedly put this comment in the wrong thread.