我创建了一个发票程序，允许用户从产品菜单中选择要购买或退货的商品。一旦用户输入了所需的项目ID和数量，程序将读取inventory.txt文件并写入UpdatedInventory.txt文件，该文件将替换inventory.txt文件。 inventory.txt文件的格式如下：
ID
item
stock
price
当我的程序运行时，它无法在UpdatedInventory.txt文件上正确打印。这里有很多代码，所以请耐心等待。
顺便说一下，如果用户制作的每笔购买都添加到列表而不是硬编码中，我觉得它会简化代码。谢谢你的帮助！
这是我的主要代码：
import InventoryFile
import os
def readFile ():
#open the file and read the lines
inventoryFile = open ('Inventory.txt', 'r')
raw_data = inventoryFile.readlines ()
#remove the new line characters
clean_data = []
for item in raw_data:
clean_item = item.rstrip ('\n')
clean_data.append (clean_item)
#read lists into objects
all_objects = []
for i in range (0, len(clean_data), 4):
ID = clean_data [i]
item = clean_data [i+1]
qty = float (clean_data [i+2])
price = float (clean_data [i+3])
#create inventory object
inventory_object = InventoryFile.Inventory (ID, item, qty, price)
all_objects.append (inventory_object)
return all_objects
def printMenu (all_data):
print ()
print ('Select an item ID to purchase or return: ')
print ()
print ('ID\tItem\t\t Quantity\t Price')
for item in all_data:
print (item)
print ()
print ('Enter another item ID or 0 to stop')
def modify ():
found = False
search = -1
while search == -1:
search = input ('Enter the ID of the product you would like to purchase: ')
try:
if search == '0':
print ('The inventory has been updated...')
break
except Exception:
search = -1
print ('ERROR: Please enter a valid number.')
else:
inventoryFile = open ('inventory.txt', 'r')
temp_file = open ('UpdatedInventory.txt', 'w')
ID = str (inventoryFile.readline ())
while ID != '':
item = str (inventoryFile.readline ())
qty = float (inventoryFile.readline ())
price = float (inventoryFile.readline())
inventory_object = InventoryFile.Inventory (ID, item, qty, price)
ID = ID.rstrip ('\n')
if ID == search:
purchase = -1
while purchase == -1:
purchaseEntry = float (input ('How many would you like to purchase? Negative numbers are returns'))
purchase = inventory_object.purchase (purchaseEntry)
if purchase is False:
purchase = -1
print ('ERROR: Insufficient stock!')
new_qty = inventory_object.restock (purchase)
transaction_object = InventoryFile.TransactionItem (ID, item, new_qty, price)
transaction_object.set_id (ID)
transaction_object.set_name (item)
transaction_object.set_qty (new_qty)
transaction_object.set_price (price)
ID = transaction_object.get_id ()
item = transaction_object.get_name ()
qty = transaction_object.get_qty ()
price = transaction_object.get_price ()
temp_file.write (ID + '\n')
temp_file.write (item + '\n')
temp_file.write (str (qty) + '\n')
temp_file.write (str (price) + '\n')
found = True
else:
temp_file.write (ID + '\n' )
temp_file.write (item + '\n')
temp_file.write (str (new_qty) + '\n')
temp_file.write (str (price) + '\n')
ID = inventoryFile.readline ()
if found:
print ('The file has been updated.')
else:
print ('That item was not found in the file.')
inventoryFile.close ()
temp_file.close ()
os.remove ('inventory.txt')
os.rename ('UpdatedInventory.txt', 'inventory.txt')
print ('Inventory has been updated.')
break
return search
def main ():
all_items = readFile ()
printMenu (all_items)
modify ()
main ()
这是我的库存类文件：
class Inventory ():
def __init__ (self, new_id, new_name, new_stock, new_price):
self.__id = new_id
self.__name = new_name
self.__stock = new_stock
self.__price = new_price
def get_id (self):
return self.__id
def get_name (self):
return self.__name
def get_stock (self):
return self.__stock
def get_price (self):
return self.__price
def restock (self, new_stock):
if new_stock < 0:
print ('ERROR')
return False
else:
self.__stock += new_stock
return True
def purchase (self, purch_qty):
if self.__stock >= purch_qty:
self.__stock -= purch_qty
return self.__stock
else:
print ('ERROR: Insufficient stock')
return False
def __str__ (self):
return self.__id + '\t' + self.__name + '\t' + \
format (self.__stock, '7.2f') + format (self.__price, '7.2f')
class TransactionItem (Inventory):
def __init__ (self, new_id, new_name, new_qty, new_price):
self.__qty = new_qty
Inventory.__init__(self, new_id, new_name, new_qty, new_price)
def get_id (self):
return self.__id
def set_id (self, new_id):
self.__id = new_id
def get_name (self):
return self.__name
def set_name (self, new_name):
self.__name = new_name
def get_qty (self):
return self.__qty
def set_qty (self, new_qty):
self.__qty = new_qty
def get_price (self):
return self.__price
def set_price (self, new_price):
self.__price = new_price
def calc_cost (self):
total = purch_qty * self.__price
def __str__ (self):
return self.__id + '\t' + self.__name + '\t' + \
format (self.__qty, '7.2f') + format (self.__price, '7.2f') + \
format (total, '7.2f')
这是我的inventory.txt文件：
244
Large Cake Pan
7
19.99
576
Assorted Sprinkles
3
12.89
212
Deluxe Icing Set
6
37.97
827
Yellow Cake Mix
3
1.99
194
Cupcake Display Board
2
27.99
285
Bakery Boxes
7
8.59
736
Mixer
5
136.94
以下是输入产品ID 244，购买数量为5后更新后的库存txt的样子。
244
Large Cake Pan
4.0
19.99
576
Assorted Sprinkles
4.0
12.89
212
Deluxe Icing Set
4.0
37.97
827
Yellow Cake Mix
4.0
1.99
194
Cupcake Display Board
4.0
27.99
285
Bakery Boxes
4.0
8.59
736
Mixer
4.0
136.94
答案 0 :(得分：0)
您是否尝试过程序？ https://docs.python.org/2/library/pdb.html或https://docs.python.org/3/library/pdb.html
在某些时候你会丢失信息
（遗憾的是很难解决这一大块代码）
答案 1 :(得分：0)
我已停用TransactionItem。这似乎有效（我已经合并了脚本文件）：
import os
class Inventory ():
def __init__(self, new_id, new_name, new_stock, new_price):
self.__id = new_id
self.__name = new_name
self.__stock = new_stock
self.__price = new_price
def get_id(self):
return self.__id
def get_name(self):
return self.__name
def get_stock(self):
return self.__stock
def get_price(self):
return self.__price
def restock(self, new_stock):
if new_stock < 0:
print('ERROR')
return False
else:
self.__stock += new_stock
return True
def purchase(self, purch_qty):
if self.__stock >= purch_qty:
self.__stock -= purch_qty
return self.__stock
else:
print('ERROR: Insufficient stock')
return False
def __str__(self):
return self.__id + '\t' + self.__name + '\t' + \
format(self.__stock, '7.2f') + format(self.__price, '7.2f')
class TransactionItem (Inventory):
def __init__(self, new_id, new_name, new_qty, new_price):
self.__qty = new_qty
Inventory.__init__(self, new_id, new_name, new_qty, new_price)
def get_id(self):
return self.__id
def set_id(self, new_id):
self.__id = new_id
def get_name(self):
return self.__name
def set_name(self, new_name):
self.__name = new_name
def get_qty(self):
return self.__qty
def set_qty(self, new_qty):
self.__qty = new_qty
def get_price(self):
return self.__price
def set_price(self, new_price):
self.__price = new_price
def calc_cost(self):
self.total = purch_qty * self.__price
def __str__(self):
return self.__id + '\t' + self.__name + '\t' + \
format (self.__qty, '7.2f') + format (self.__price, '7.2f') + \
format(self.total, '7.2f')
def readFile():
# open the file and read the lines
inventoryFile = open('Inventory.txt', 'r')
raw_data = inventoryFile.readlines()
# remove the new line characters
clean_data = []
for item in raw_data:
clean_item = item.rstrip('\n')
clean_data.append(clean_item)
# read lists into objects
all_objects = []
for i in range(0, len(clean_data), 4):
ID = clean_data[i]
item = clean_data[i + 1]
qty = float(clean_data[i + 2])
price = float(clean_data[i + 3])
# create inventory object
inventory_object = Inventory(ID, item, qty, price)
all_objects.append(inventory_object)
return all_objects
def printMenu(all_data):
print()
print('Select an item ID to purchase or return: ')
print()
print('ID\tItem\t\t Quantity\t Price')
for item in all_data:
print(item)
print()
print('Enter another item ID or 0 to stop')
def modify():
found = False
search = -1
while search == -1:
search = input(
'Enter the ID of the product you would like to purchase: ')
try:
if search == '0':
print('The inventory has been updated...')
break
except Exception:
search = -1
print('ERROR: Please enter a valid number.')
else:
inventoryFile = open('inventory.txt', 'r')
temp_file = open('UpdatedInventory.txt', 'w')
ID = str(inventoryFile.readline())
while ID != '':
item = str(inventoryFile.readline())
qty = float(inventoryFile.readline())
price = float(inventoryFile.readline())
inventory_object = Inventory(ID, item, qty, price)
ID = ID.rstrip('\n')
item = item.rstrip('\n')
if ID == search:
purchase = -1
while purchase == -1:
purchaseEntry = float(
input('How many would you like to purchase? Negative numbers are returns'))
purchase = inventory_object.purchase(purchaseEntry)
if purchase is False:
purchase = -1
print('ERROR: Insufficient stock!')
#new_qty = inventory_object.restock(purchase)
#transaction_object = TransactionItem(
# ID, item, new_qty, price)
#transaction_object.set_id(ID)
#transaction_object.set_name(item)
#transaction_object.set_qty(new_qty)
#transaction_object.set_price(price)
#ID = transaction_object.get_id()
#item = transaction_object.get_name()
#qty = transaction_object.get_qty()
#price = transaction_object.get_price()
qty = inventory_object.get_stock()
price = inventory_object.get_price()
temp_file.write(ID + '\n')
temp_file.write(item + '\n')
temp_file.write(str(int(qty)) + '\n')
temp_file.write(str(price) + '\n')
found = True
else:
temp_file.write(ID + '\n')
temp_file.write(item + '\n')
temp_file.write(str(int(qty)) + '\n')
temp_file.write(str(price) + '\n')
ID = inventoryFile.readline()
if found:
print('The file has been updated.')
else:
print('That item was not found in the file.')
inventoryFile.close()
temp_file.close()
os.remove('inventory.txt')
os.rename('UpdatedInventory.txt', 'inventory.txt')
print('Inventory has been updated.')
break
return search
def main():
all_items = readFile()
printMenu(all_items)
modify()
main()
我希望它有所帮助！