A permanent list change(Save python file) - python-3.x

Question

I am a noob in python and i need help.I have made a phonebook where you can add the contacts.But the problem is that when i exit the program the changes to the list are not saved.I want the user to be able to make permanent changes to the list.I have seen posts about a file=open("something",'w') code to do this(I think) but i dont know where to insert this code and i dont really understand what it is.Could someone help me understand what this is about..Here is the full code:
name = ["ranga","hari"]
number = [9895497777,9]
book = {name[0]:number[0],name[1]:number[1]}
def search():
print("Contacts:")
for x in book:
print(x,':',book[x])
while 1:
count = 0
a = 0
ch1 = input("search: ")
try:
ch1 = int(ch1)
except ValueError:
while a < len(name):
result = name[a].find(ch1)
if result == -1:
a = a + 1
else:
print(name[a],number[a])
a = a + 1
count = count + 1
if count == 0:
print("Not available.Try again")
continue
else:
break
ch1 = str(ch1)
while a < len(number):
sumber = str(number[a])
result = sumber.find(ch1)
if result == -1:
a = a + 1
else:
print(name[a],number[a])
a = a + 1
count += 1
if count == 0:
print("Not available.try again")
continue
else:
break
def add():
print("What is the name of the contact you want to add?")
name1 = input()
name.append(name1)
while 1:
print("What is the number of this contact?")
number1 = input()
try:
number1 = int(number1)
except ValueError:
print("Please type a number..")
continue
number.append(number1)
book[name1] = number1
break
def remoe():
print("Reference:")
for x in book:
print(x,':',book[x])
while 1:
print("What is the name of the contact you want to remove?")
name2 = input()
if name2 in book:
increment = name.index(name2)
name.pop(increment)
number.pop(increment)
del book[name2]
break
else:
print("Not available.Please try again")
while 1:
print("Contacts:")
for x in book:
print(x, ':', book[x])
print("\nWhat do you want to do?\n1.Search for a person\n2.edit the phone book\n3.exit")
choice = input()
try:
choice = int(choice)
except ValueError:
print("Type 1,2 or 3")
continue
if choice == 1:
search()
elif choice == 2:
while 1:
print("Do you want to:\n1.Add a contact\n2.Remove a contact\n3.Go back to main menu")
ch2 = input()
if ch2 in['3']:
break
else:
try:
ch2 = int(ch2)
except ValueError:
print("Type 1 or 2..")
if ch2 == 1:
add()
elif ch2 == 2:
remoe()
elif choice == 3:
exit()
else:
print("Type 1,2 or 3")
I appreciate the help.

Answer 1

When you choose to add a contact, it does properly add the name and number to the list. But, that is it.
When you re-run the program, the list gets re-assigned due to the first 2 lines of your code:
name = ["ranga","hari"]
number = [9895497777,9]
So, you won't see the last changes.
This is where you should maintain a file which lives outside the scope of your code, rather than a list.
You can modify your add function like this:
def add():
print("What is the name of the contact you want to add?")
name1 = input()
#name.append(name1)
# Just add the name1 variable's value to the file
with open('contacts_list.txt', 'a+') as f:
f.write(name1 + '\n')
while 1:
print("What is the number of this contact?")
number1 = input()
try:
number1 = int(number1)
except ValueError:
print("Please type a number..")
continue
#number.append(number1)
# Similarly, append the number1 variable's value to file again.
with open('contacts_list.txt', 'w+') as f:
f.write(number1)
#book[name1] = number1
with open('contacts_list.txt', 'r') as f:
print(f.read())
break
Note: You would also need to change the other functions search and remove to read and write from the file. I've just given you a taste of how things are done. You need to modify your code and make it work.
Let me know if it helps.

Answer 2

I took your advice and made a new text file but i still did not know how to do it but after reading ur answers i understood and at last i came to this..
removelist = []
def search():
while 1:
search = str(input("Search: "))
if search not in["exit", "Exit"]:
with open('output.txt', 'r+') as f:
line = f.readline()
while line:
data = line.find(search)
if not data == -1:
print(line.rstrip('\n'))
line = f.readline()
else:
line = f.readline()
else:
break
f.close()
def add():
print("Type the name of the contact:")
name = input()
while 1:
print("Type the number of this contact:")
number = input()
try:
number = int(number)
except ValueError:
print("Please type a number")
continue
number = str(number)
with open('output.txt', 'a+') as f:
f.write('\n' + name +' ' + number)
break
def remoe(): #this is where the problem comes in
while 1:
remove = str(input("Remove: "))
with open('output.txt', 'r+') as f:
line = f.readline()
while line:
if not remove in["Remove", "remove"]:
removelist.clear()
data = line.find(remove)
if not data == -1:
removelist.append(line) #This saves all the lines coming from the search to a
print(removelist) #removelist which can be accessed when you type in remove
line = f.readline() #But the problem is that if there is a \n at the end of the
else: #string then the remove function does not work
line = f.readline()
else:
print(removelist)
with open('output.txt', 'r') as f:
d = f.readlines()
f.close()
with open('output.txt', 'w') as f:
for i in d:
if i not in removelist:
f.write(i)
f.truncate()
f.close()
break
while 1:
with open('output.txt', 'r') as f:
data = f.read()
print("Contacts:")
print(data)
print('''What do you want to do?
1.Search for a contact
2.Edit contacts
3.Exit''')
f.close()
choice = input()
if choice in["1"]:
search()
elif choice in["2"]:
while 1:
print('''What do you wanna do:
1.Add a contact
2.Remove a contact
3.Exit to main menu''')
ch1 = input()
if ch1 in["1"]:
add()
elif ch1 in["2"]:
remoe()
elif ch1 in["3"]:
break
else:
print("Please type 1,2 or 3")
elif choice in[3]:
print("Ok bye")
else:
print("Please type 1,2 or 3")
Now the problem seems to be the remove function..if i try to remove a line with \n at the end of it then it wont work while the opp. seems to work.Any guess what i am doing here?
And thanks for the help Mayank porwal

Answer 3

At the first you should know name = ["ranga","hari"], number = [9895497777,9] that you have defined are in the code and you can not change those value, and after exit() they will reset to default value.
you should use of file (for example .txt file) in this issue:
1. you must create a .txt file in your project (for example Contacts.txt)
2. and write your information in there (for example in first line: Kourosh +98938....)
3. at the first step in your program you must read Contact.txt and load it in a structure like a list or dictionary (for example
>>> with open('workfile') as f:
... read_data = f.read()
>>> f.closed
)
4.now you can edit, add, remove structure.
5.and finally you can write structure in the file, before exit()
for example:
>>> with open('workfile') as f:
... f.write(s)
>>> f.closed