如何在输入中同时使用float nub和words？

Question

cheese = float(input("Enter cheese order weight (numeric value): "))

if cheese >= 100:
    print(cheese,"is more than currently available stock ")
elif cheese <= 0.15:
    print(cheese,"is below minimum order amount")
elif cheese >= 0.16 <= 99:
    print(cheese," costs $",cheese * 7.99,sep = "")
else:
    print(cheese,"Is invlide, please try agin")

每次我添加一个字母时，我都会得到一个错误。我希望能够添加float nub和单词，这样我就可以使用else语句。

Answer 1

我不知道“矮子”是什么意思？但您需要将其放入循环中，并使用try和except处理错误

cheese_weight = None
# Repeat until there is a valid value for cheese_weight
while not cheese_weight:
    # Step 1: get some user input
    raw_input = input("Enter cheese order weight (numeric value): ")
    # Step 2: try convert this input to a float
    try:
        cheese_weight = float(raw_input)
    # Step 3: handle the error if there is one
    except ValueError as err:
        print("The cheese weight must be a numeric value.)

请注意，如果float(raw_input)引发错误，cheese_weight将不会获得新值，因此循环将再次运行。如果值解析为浮点型，那么cheese_weight将有一个不是None的值，因此循环将结束。