英文:
Why doesn't Control-D cause an EOFError in python?
问题
我正在尝试实现一个程序，允许用户下订单，提示他们输入商品，每次输入一行，直到用户输入control-d（这是结束程序输入的常见方式）。
然而，当我按下control-d时，在我的终端上会显示"^D"，并且不会退出，而是当我在它之后点击Enter键时，它不会导致EOFError退出程序。
def main():
menu = {
"Baja Taco": 4.00,
"Burrito": 7.50,
"Bowl": 8.50,
"Nachos": 11.00,
"Quesadilla": 8.50,
"Super Burrito": 8.50,
"Super Quesadilla": 9.50,
"Taco": 3.00,
"Tortilla Salad": 8.00
}
total = 0;
while True:
try:
item = input("商品: ").title()
except EOFError as e:
print("\n")
break
except KeyError as k:
print("发生键错误")
else:
if menu.get(item) != None:
total+= menu.get(item)
print(f'总计: ${total:.2f}')
main()
我期望在按下control-d时退出循环，但它只是继续循环。
英文:
Im trying to implement a program that enables a user to place an order, prompting them for items, one per line, until the user inputs control-d (which is a common way of ending one’s input to a program).
however when I press control d, in my terminal this appears "^D" and it doesn't exit, instead when i click enter after it it doesn't cause the EOFError to exit the program.
def main():
menu = {
"Baja Taco": 4.00,
"Burrito": 7.50,
"Bowl": 8.50,
"Nachos": 11.00,
"Quesadilla": 8.50,
"Super Burrito": 8.50,
"Super Quesadilla": 9.50,
"Taco": 3.00,
"Tortilla Salad": 8.00
}
total = 0;
while True:
try:
item = input("Item: ").title()
except EOFError as e:
print("\n")
break
except KeyError as k:
print("key error occured")
else:
if menu.get(item) != None:
total+= menu.get(item)
print(f'Total: ${total:.2f}')
main()
I expected to exit loop when control d is pressed, but it just continues the loop
答案1
得分: 2
正如@chepner提到的，
> 您的终端似乎没有将Ctrl-d解释为关闭标准输入的信号。
对于您的规格，即Windows上的VScode IDE，默认情况下它不会将Ctrl-D（*Nix）序列或Ctrl-Z（Windows）序列解释为文件结束（EOF）。
此外，对于Ctrl-C，您需要检查它是否中断了进程。 中断信号和EOF信号是不同的。对于Ctrl-C序列，print("n"); break 不会发生。
我不确定，但要在Windows上的VScode IDE中使用Ctrl-Z作为EOF，请查看此答案。
英文:
As @chepner mentioned,
> Your terminal doesn't appear to be interpreting Ctrl-d as a signal to close standard input.
For your spec, which is VScode IDE on Windows, It doesn't interpret Ctrl-D(*Nix) sequence or Ctrl-Z(Windows) sequence as an EOF(End of File) in default.
Also, for Ctrl-C, you need to check whether it interrupts the process. The interrupt signal and EOF signal differ. With the Ctrl-C sequence, print("\n"); break won't happen.
I'm not sure, but to use Ctrl-Z as an EOF in VScode IDE on Windows, check this answer.
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