我正在为期末考试而学习,这是我错过的测验问题。 我需要有关getTotal方法的大部分帮助。我需要遍历列表,找到每个项目的价格,将价格添加到总计并返回总计。我在循环中挣扎,我不确定如何从列表中拉出第二项。.[1] ??我已经尝试了很多方法,但感到沮丧。
如果有人愿意帮助我,那就太好了。我还在学习,而且是新手,所以对我放轻松,但我真的很想学习它。这可能并不像我想象的那么难,但 Ill 正在等待一些输入。谢谢!
class Item:
def __init__(self, name, price):
self.name = name
self.price = price
def getPrice(self):
return self.price
def getName(self):
return self.name
class Cart:
def __init__(self, list):
self.list = []
def addItem(self, item):
self.list.append(self.list)
def getTotal(self):
total = 0
for item in self.list:
name, price = item # or price = item[1]
total = total + price
def getNumItems(self):
count = 0
for c in range(self.list):
count = self.list + 1
return count
def removeItem(self, item)
#removes the item from the cart's item list
def main():
item1 = Item("Banana", .69)
item2 = Item("Eggs", 2.39)
item3 = Item("Donut", .99)
c = Cart()
c.addItem(item1)
c.addItem(item2)
c.addItem(item3)
print "You have %i items in your cart for a total of $%.02f" %(c.getNumItems(), c.getTotal())
c.removeItem(item3)
print "You have %i items in your cart for a total of $%.02f" % (c.getNumItems(), c.getTotal())
main()
这里给出了时间,我更改了代码,现在它是功能齐全的购物车
class Item(object):
def __init__(self, unq_id, name, price, qty):
self.unq_id = unq_id
self.product_name = name
self.price = price
self.qty = qty
class Cart(object):
def __init__(self):
self.content = dict()
def update(self, item):
if item.unq_id not in self.content:
self.content.update({item.unq_id: item})
return
for k, v in self.content.get(item.unq_id).iteritems():
if k == 'unq_id':
continue
elif k == 'qty':
total_qty = v.qty + item.qty
if total_qty:
v.qty = total_qty
continue
self.remove_item(k)
else:
v[k] = item[k]
def get_total(self):
return sum([v.price * v.qty for _, v in self.content.iteritems()])
def get_num_items(self):
return sum([v.qty for _, v in self.content.iteritems()])
def remove_item(self, key):
self.content.pop(key)
if __name__ == '__main__':
item1 = Item(1, "Banana", 1., 1)
item2 = Item(2, "Eggs", 1., 2)
item3 = Item(3, "Donut", 1., 5)
cart = Cart()
cart.update(item1)
cart.update(item2)
cart.update(item3)
print "You have %i items in your cart for a total of $%.02f" % (cart.get_num_items(), cart.get_total())
cart.remove_item(1)
print "You have %i items in your cart for a total of $%.02f" % (cart.get_num_items(), cart.get_total())
输出为:
You have 8 items in your cart for a total of $8.00
You have 7 items in your cart for a total of $7.00
for getTotal:
def getTotal(self):
total = 0
for item in self.list:
name, price = item # or price = item[1]
total = total + price
顺便说一句,您的addItem和getNumItems方法也是错误的。由于它是最终的,您应该尝试了解您正在做什么。