作业：
用户入口：
1. 商品信息存在文件里
2. 已够商品，余额记录
商家入口
2. 可以添加商品，修改商品价格
import os, sys, copy,time
products_db = "simple_shop_system_products.db"
cart_db = "simple_shop_system_carts.db"
# get product data from database
def read_products_from_db(database_name):
if os.path.exists(database_name):
with open(database_name,"r") as fs:
return (True, fs.read())
else:
return (False, "Products database not exist !")
# write product data into database
def write_products_to_db(database_name, product_data):
if os.path.exists(database_name):
with open(database_name, "w") as fs:
fs.write(product_data)
fs.flush()
return (True, "Save Successfully")
else:
return (False, "Product's database not exist !")
# show system info and entrance to user
def show_system_info():
print("*" * 60)
print("*%s*" % " ".center(58))
print("*%s*" % "Shopping System".center(58))
print("*%s*" % "v1.00".center(58))
print("*%s*" % "1.For Host user 2.For Customer user".center(58))
print("*%s*" % " ".center(58))
print("*" * 60)
def show_error(error_inio):
print("Error:%s" % error_inio)
def show_pass(pass_info):
print("Pass:%s" % pass_info)
# check format for input data:
def input_and_check(right_data, prompt_data, flag_type):
# flag is True for string else for number
while True:
data = input(prompt_data).strip()
if not data:
show_error("Input is Null!")
continue
if flag_type == False:
if data.isdigit():
data = int(data)
else:
show_error("Input error!")
continue
if len(right_data) > 0:
if not data in right_data:
show_error("Input error!")
continue
else:
return data
else:
return data
def show_products_list(product_data, title_info):
print("*" * 60)
print("|| %s" % title_info)
print("-" * 60)
print("|{name}|{price}|{balance}|".format(name="Name".center(25, " "), price="Price".center(15, " "), balance="Balance".center(16, " ")))
print("-" * 60)
for n in product_data:
# print(n, product_data[n]["price"], product_data[n]["stocks"])
print("|{name}|{price}|{balance}|".format(name=n.center(25, " "), price=str(product_data[n]["price"]).center(15, " "), balance=str(product_data[n]["stocks"]).center(16, " ")))
print("-" * 60)
def host_user_func():
# get data from database;
data = read_products_from_db(products_db)
if data[0] == True:
product_data = eval(data[1])
else:
sys.exit("Error:%s"% data[1])
while True:
show_products_list(product_data, "Products List: ")
print("*" * 60)
print("*%s*" % " 1. Edit Price".ljust(58, " "))
print("*%s*" % " 2. Add Product".ljust(58, " "))
print("*%s*" % " 3. Remove Products".ljust(58, " "))
print("*%s*" % " 4. Back To Home".ljust(58, " "))
print("*%s*" % " 5. Exit System".ljust(58, " "))
print("*" * 60)
select_data = input_and_check((1, 2, 3, 4, 5), "Please select: ", False)
# for change product price
if select_data == 1:
product_selected = input_and_check(product_data, "Select Products: ", True)
product_info = {product_selected: copy.deepcopy(product_data[product_selected])}
show_products_list(product_info, "Product Selected:")
new_price = input_and_check((), "Input New Price: ", False)
product_info[product_selected]["price"] = new_price
show_products_list(product_info, "Product Changed:")
product_confirm = input_and_check(("Y", "N"), "Please Confirm (Y/N): ", True)
if product_confirm == "Y":
product_data[product_selected] = product_info[product_selected]
show_pass("the %s's price changed Successfully!" % product_selected)
else:
show_error("the %s's price changed Fail!" % product_selected)
print("=" * 60)
print()
# for add new products
elif select_data == 2:
new_product = input_and_check((), "New Product's Name: ", True)
new_price = input_and_check((), "New Product's Price:", False)
new_stocks = input_and_check((), "New Product's Stocks: ", False)
product_info = {new_product: {'price': new_price, 'stocks': new_stocks}}
show_products_list(product_info, "New Products:")
product_confirm = input_and_check(("Y", "N"), "Please Confirm (Y/N): ", True)
if product_confirm == "Y":
if new_product in product_data:
product_info[new_product]["stocks"] += product_data[new_product]["stocks"]
product_data[new_product] = product_info[new_product]
show_pass("the %s' Create Successfully!" % new_product)
else:
show_error("the %s Create changed Fail!" % new_product)
print("=" * 60)
# for products delete
elif select_data == 3:
product_delete = input_and_check(product_data, "Select Products: ", True)
product_info = {product_delete: product_data[product_delete]}
show_products_list(product_info, "Product Selected:")
product_confirm = input_and_check(("Y", "N"), "Please Confirm (Y/N): ", True)
if product_confirm == "Y":
del product_data[product_delete]
show_pass("the %s'Remove Successfully!" % product_delete)
else:
show_error("the %s Remove Fail!" % product_delete)
print("=" * 60)
# for back to home page
elif select_data == 4:
confirm_data = input_and_check(("Y", "N"), "Save Data ? (Y/N):", True)
if confirm_data.upper() == "Y":
write_status = write_products_to_db(products_db, str(product_data))
if write_status[0] == True:
print(write_status[1])
break
else:
sys.exit(write_status[1])
else:
break
# for System exiting ...
else:
confirm_data = input_and_check(("Y", "N"), "Save Data ? (Y/N):", True)
if confirm_data.upper() == "Y":
write_status = write_products_to_db(products_db, str(product_data))
if write_status[0] == True:
print(write_status[1])
sys.exit("System exiting....")
else:
sys.exit(write_status[1])
else:
sys.exit("System exiting....")
def customer_user_func():
# get data from database;
data1 = read_products_from_db(products_db)
if data1[0] == True:
product_data = eval(data1[1])
else:
sys.exit("Error:%s"% data1[1])
# get data from carts
data2 = read_products_from_db(cart_db)
if data2[0] == True:
cart_data = eval(data2[1])
else:
sys.exit("Error:%s"% data2[1])
while True:
show_products_list(product_data, "Products List: ")
product_selected = input_and_check(product_data, "Select Product: ", True)
cart_data.append(product_selected)
show_pass("Add %s into cart successfully !" % product_selected)
print("*" * 60)
print("*%s*" % "1.Continue 2.Charge 3. Exit System".center(58, " "))
print("*" * 60)
select_action = input_and_check((1, 2, 3), "Select : ", False)
if select_action == 1:
continue;
elif select_action == 2:
cart_info = list(set(cart_data))
print("")
print("*" * 60)
print("|%s|" % "Products List In Cart".center(58, " "))
print("-" * 60)
print("|{id}|{name}|{price}|{quantity}|{total}|".format(id="ID".center(5, " "), name="Name".center(19, " "),
price="Price".center(10, " "), quantity="Quantity".center(10, " "), total="Total".center(10, " ")))
print("-" * 60)
total_price = 0
for c_id, c_name in enumerate(cart_info):
print("|{id}|{name}|{price}|{quantity}|{total}|".format(id=str(c_id).center(5, " "), name=c_name.center(19, " "),
price=str(product_data[c_name]["price"]).center(10, " "), quantity=str(cart_data.count(c_name)).center(10, " "),
total=str(product_data[c_name]["price"] * cart_data.count(c_name)).center(10, " ")))
print("-" * 60)
total_price += product_data[c_name]["price"] * cart_data.count(c_name)
print("|{data_name}|{date_value}|{total_name}|{total_value}|".format(data_name="Date".center(10, " "),date_value=str(time.strftime('%Y-%m-%d',time.localtime())).center(15, " "),
total_name="Total".center(10, " "), total_value=str(total_price).center(20," ")))
print("-" * 60)
print()
print("*" * 60)
print("*%s*" % "1.Back to Menu 2.Pay Account".center(58, " "))
print("*" * 60)
select_action = input_and_check((1, 2), "Select : ", False)
if select_action == 1:
continue;
else:
confirm_data = input_and_check(("Y", "N"), "Confirm Payment ？(Y/N):", True)
if confirm_data == "Y":
cart_data.clear()
write_status = write_products_to_db(cart_db, str(cart_data))
show_pass("Pay for successfully !")
break
else:
show_error( "Pay for Fail!")
continue;
else:
confirm_data = input_and_check(("Y", "N"), "Save Cart ? (Y/N):", True)
if confirm_data == "Y":
write_status = write_products_to_db(cart_db, str(cart_data))
if write_status[0] == True:
sys.exit(write_status[1])
else:
sys.exit(write_status[1])
else:
sys.exit("System exit....")
def main():
while True:
show_system_info()
sel_data = input_and_check((1, 2),"please select:", False)
# if sel_data = 1 for Host User, else for customer user;
if sel_data == 1:
host_user_func();
else:
customer_user_func();
if __name__ == "__main__":
main()