Question

运行此操作时遇到一些麻烦。基本上我只想得到一笔金额，如果它超过50免费送货，少于10美元的额外费用。我继续收到关于将浮点数转换为str implicity的错误？我认为我的输入应该被视为浮动？

#declare flags
shippingCharge = 10
freeShipping = False
#Get number and convert to float?
purchaseAmount = float(input("\nHow much is the purchase amount? "))

if (purchaseAmount) >= 50 : 
    freeShipping = True
    print("Your purchase amount is " + purchaseAmount + "$ and shipping is free!")
else : 
    print("Your purchase amount is " + purchaseAmount + "$ and shipping is " + shippingCharge + "$.")
    purchaseAmount = shippingCharge + purchaseAmount
    print("Your new total is " + purchaseAmount)
print ("Have a nice day and thank you for shopping with us.")

Answer 1

问题在于您的打印声明：

print("Your purchase amount is " + purchaseAmount + "$ and shipping is free!")

您在没有转换的情况下连接字符串和浮点数，请尝试向变量添加str（）强制转换：

即：

print("Your purchase amount is " + str(purchaseAmount) + "$ and shipping is free!")

您还可以使用格式：

print("Your purchase amount is {0}$ and shipping is free!".format(purchaseAmount))

Answer 2

因为Python是一种强类型语言：

CamelCaseNamingStrategy

您需要明确地将类型转换为字符串。它不会故意自动为你做。

Answer 3

只需用str（purchaseAmount）替换purchaseAmount，你就可以了。

How much is the purchase amount? 50
Your purchase amount is 50.0$ and shipping is free!
Have a nice day and thank you for shopping with us.

Answer 4

您输入的是浮点数，因此无法与字符串连接。你必须插入浮动。

 print('Your purchase amount is ${} and shipping is free!'.format(purchaseAmount))

为什么我无法隐式地将float转换为str？

4 个答案: