Python 中的 "Do you want to continue?" 类型案例有问题
Trouble with "Do you want to continue?" type cases in Python
场景如下：
我有一个功能，要求用户输入 select m 列表中的 n[=39] 项=] 项目（给定 m <= n）。仅供参考，如果他愿意，他可能会输入错误的值，在这种情况下，系统会询问他是否要重新开始，但如果他输入正确的值，则一切正常。我被前一部分卡住了。
这是我的代码，我知道这是错误的，所以不需要惩罚我！
column_names = ["DWUXZ", "bKDoH", "erLlI", "QJAfR", "dAfNn", "kpwGt", "fuDmY", "WoTau", "qrFaZ", "ZGSkx"] #The list to choose the items from
def newfunc():
print (f"Here is the list of columns to choose from: {column_names}\n"
args = input ("Enter column names separated by comma (Hit enter to select all columns).\n").split(',')
userinputs_notfound = [] #This will hold the wrong entries entered by the user.
for arg in args:
if arg.replace(" ", "") not in column_names:
userinputs_notfound.append(arg.replace(" ", ""))
if len(userinputs_notfound) == 0:
pass
else:
while input("Do you want to continue? [Y/n]: ").lower() == 'y':
newfunc() #Recursively calling the function
newfunc() #Calling the function.
我无法正确理解 while 部分。简而言之，这是我希望它执行的操作：
- 用户可以选择 select 给定列表中的字符串（称为 column_names）
- 他故意输入错误的值
- 脚本显示“未找到这些条目。您想再试一次吗？[Y/n]”
- 当用户点击 Y 时，它返回并再次执行整个操作。
- 如果他selects 否，则退出循环
对于我来说，我无法做到这一点。
非常感谢任何帮助。
整个 body 应该在一个 while 循环中，一旦输入正确，您就会跳出该循环。不要像这样无限制地使用递归。
column_names = set(["DWUXZ", "bKDoH", "erLlI", "QJAfR", "dAfNn", "kpwGt", "fuDmY", "WoTau", "qrFaZ", "ZGSkx")
def newfunc():
while True:
print (f"Here is the list of columns to choose from: {column_names}\n"
args = input ("Enter column names separated by comma (Hit enter to select all columns).\n").split(',')
if all(arg.replace(" ", "") in column_names for arg in args):
break
missing = set(args) - column_names
if missing:
print(f"Missing: {missing}")
response = input("Do you want to try again?")
if response.lower() == "n":
break
要么将整个函数体放在 for 循环中，并省略递归调用：
def foo():
while x:
do_stuff
change_x
或省略 while 循环并使用条件 if 语句保持递归：
def foo():
do_stuff
if condition:
foo()
否则您将继续调用该函数，因此您需要转义您在程序 运行 期间创建的每个 while input() == 'y' 循环，无论可能有多少循环。
至于'hit enter to keep select all columns:
if arg == ['']:
arg = column_names
对照 [''] 检查，因为您拆分了用户输入。
对您的代码进行了一些重构：
（也解决了 'enter to select all columns' 问题。）
# The list to choose the items from
column_names = ["DWUXZ", "bKDoH", "erLlI", "QJAfR", "dAfNn", "kpwGt",
"fuDmY", "WoTau", "qrFaZ", "ZGSkx"]
def get_input():
print(f"Here is the list of columns to choose from: {column_names}\n")
args = input("Enter column names separated by comma "
"(Hit enter to select all columns).\n").strip().split(',')
return args
while True:
args = get_input()
if len(args) == 1 and args[0] == '': # pressed enter
print('OK. Selected all columns')
break
# This will hold the wrong entries entered by the user.
userinputs_notfound = []
for arg in args:
if arg.replace(" ", "") not in column_names:
userinputs_notfound.append(arg.replace(" ", ""))
if not userinputs_notfound:
print('OK')
break
should_quit = input("Do you want to continue? [Y/n]: ").lower() == 'n'
if should_quit is True:
break
输出：
Here is the list of columns to choose from: ['DWUXZ', 'bKDoH', 'erLlI', 'QJAfR', 'dAfNn', 'kpwGt', 'fuDmY', 'WoTau', 'qrFaZ', 'ZGSkx']
Enter column names separated by comma (Hit enter to select all columns).
DWUXZ, bKDoH
OK
Here is the list of columns to choose from: ['DWUXZ', 'bKDoH', 'erLlI', 'QJAfR', 'dAfNn', 'kpwGt', 'fuDmY', 'WoTau', 'qrFaZ', 'ZGSkx']
Enter column names separated by comma (Hit enter to select all columns).
fda, fdax
Do you want to continue? [Y/n]: n
Here is the list of columns to choose from: ['DWUXZ', 'bKDoH', 'erLlI', 'QJAfR', 'dAfNn', 'kpwGt', 'fuDmY', 'WoTau', 'qrFaZ', 'ZGSkx']
Enter column names separated by comma (Hit enter to select all columns).
fda, dax
Do you want to continue? [Y/n]: y
Here is the list of columns to choose from: ['DWUXZ', 'bKDoH', 'erLlI', 'QJAfR', 'dAfNn', 'kpwGt', 'fuDmY', 'WoTau', 'qrFaZ', 'ZGSkx']
Enter column names separated by comma (Hit enter to select all columns).
Here is the list of columns to choose from: ['DWUXZ', 'bKDoH', 'erLlI', 'QJAfR', 'dAfNn', 'kpwGt', 'fuDmY', 'WoTau', 'qrFaZ', 'ZGSkx']
Enter column names separated by comma (Hit enter to select all columns).
OK. Selected all columns
column_names = ["DWUXZ", "bKDoH", "erLlI", "QJAfR", "dAfNn", "kpwGt", "fuDmY", "WoTau", "qrFaZ", "ZGSkx"]
def newfunc():
print (f"Here is the list of columns to choose from: {column_names}\n") //correction
args = input("Enter column names separated by comma (Hit enter to select all columns).\n").split(',')
userinputs_notfound = [] #This will hold the wrong entries entered by the user.
for arg in args:
if arg.replace(" ", "") not in column_names:
userinputs_notfound.append(arg.replace(" ", ""))
if len(userinputs_notfound) == 0:
pass
else:
if input("Do you want to continue? [Y/n]: ").lower() == 'y': //correction no need of while
newfunc()
newfunc() #Calling the function.
这个适用于 python 3.8+
# The list to choose from
col_names = ["DWUXZ", "bKDoH", "erLlI", "QJAfR", "dAfNn", "kpwGt", "fuDmY", "WoTau", "qrFaZ", "ZGSkx"]
def newFunc():
# Print all the available column names.
print("List of columns to choose from:\n", *col_names, sep = '\n')
# Filter out the missing names (if any) and ask for the prompt.
# The anonymous function inside lambda match against the empty
# string when the user chooses to select all.
while missing := list(filter(lambda name: name and name not in col_names,
input("\nEnter column names separated by comma (Hit enter to select all): ").split(','))):
print("Missing:", *missing, sep = '\n')
# Break the loop for any of the negetive response.
if input("\nDo you want to continue? ").lower() in ['n', "no", "nope", "nah"]:
break
# Implement here your logic when no missing is found.
# Call the function.
newFunc()
在赋值运算符的帮助下 := 我们只用了几行代码就做到了。
场景如下：
我有一个功能，要求用户输入 select m 列表中的 n[=39] 项=] 项目（给定 m <= n）。仅供参考，如果他愿意，他可能会输入错误的值，在这种情况下，系统会询问他是否要重新开始，但如果他输入正确的值，则一切正常。我被前一部分卡住了。
这是我的代码，我知道这是错误的，所以不需要惩罚我！
column_names = ["DWUXZ", "bKDoH", "erLlI", "QJAfR", "dAfNn", "kpwGt", "fuDmY", "WoTau", "qrFaZ", "ZGSkx"] #The list to choose the items from
def newfunc():
print (f"Here is the list of columns to choose from: {column_names}\n"
args = input ("Enter column names separated by comma (Hit enter to select all columns).\n").split(',')
userinputs_notfound = [] #This will hold the wrong entries entered by the user.
for arg in args:
if arg.replace(" ", "") not in column_names:
userinputs_notfound.append(arg.replace(" ", ""))
if len(userinputs_notfound) == 0:
pass
else:
while input("Do you want to continue? [Y/n]: ").lower() == 'y':
newfunc() #Recursively calling the function
newfunc() #Calling the function.
我无法正确理解 while 部分。简而言之，这是我希望它执行的操作：
- 用户可以选择 select 给定列表中的字符串（称为 column_names）
- 他故意输入错误的值
- 脚本显示“未找到这些条目。您想再试一次吗？[Y/n]”
- 当用户点击 Y 时，它返回并再次执行整个操作。
- 如果他selects 否，则退出循环
对于我来说，我无法做到这一点。
非常感谢任何帮助。
整个 body 应该在一个 while 循环中，一旦输入正确，您就会跳出该循环。不要像这样无限制地使用递归。
column_names = set(["DWUXZ", "bKDoH", "erLlI", "QJAfR", "dAfNn", "kpwGt", "fuDmY", "WoTau", "qrFaZ", "ZGSkx")
def newfunc():
while True:
print (f"Here is the list of columns to choose from: {column_names}\n"
args = input ("Enter column names separated by comma (Hit enter to select all columns).\n").split(',')
if all(arg.replace(" ", "") in column_names for arg in args):
break
missing = set(args) - column_names
if missing:
print(f"Missing: {missing}")
response = input("Do you want to try again?")
if response.lower() == "n":
break
要么将整个函数体放在 for 循环中，并省略递归调用：
def foo():
while x:
do_stuff
change_x
或省略 while 循环并使用条件 if 语句保持递归：
def foo():
do_stuff
if condition:
foo()
否则您将继续调用该函数，因此您需要转义您在程序 运行 期间创建的每个 while input() == 'y' 循环，无论可能有多少循环。
至于'hit enter to keep select all columns:
if arg == ['']:
arg = column_names
对照 [''] 检查，因为您拆分了用户输入。
对您的代码进行了一些重构：
（也解决了 'enter to select all columns' 问题。）
# The list to choose the items from
column_names = ["DWUXZ", "bKDoH", "erLlI", "QJAfR", "dAfNn", "kpwGt",
"fuDmY", "WoTau", "qrFaZ", "ZGSkx"]
def get_input():
print(f"Here is the list of columns to choose from: {column_names}\n")
args = input("Enter column names separated by comma "
"(Hit enter to select all columns).\n").strip().split(',')
return args
while True:
args = get_input()
if len(args) == 1 and args[0] == '': # pressed enter
print('OK. Selected all columns')
break
# This will hold the wrong entries entered by the user.
userinputs_notfound = []
for arg in args:
if arg.replace(" ", "") not in column_names:
userinputs_notfound.append(arg.replace(" ", ""))
if not userinputs_notfound:
print('OK')
break
should_quit = input("Do you want to continue? [Y/n]: ").lower() == 'n'
if should_quit is True:
break
输出：
Here is the list of columns to choose from: ['DWUXZ', 'bKDoH', 'erLlI', 'QJAfR', 'dAfNn', 'kpwGt', 'fuDmY', 'WoTau', 'qrFaZ', 'ZGSkx']
Enter column names separated by comma (Hit enter to select all columns).
DWUXZ, bKDoH
OK
Here is the list of columns to choose from: ['DWUXZ', 'bKDoH', 'erLlI', 'QJAfR', 'dAfNn', 'kpwGt', 'fuDmY', 'WoTau', 'qrFaZ', 'ZGSkx']
Enter column names separated by comma (Hit enter to select all columns).
fda, fdax
Do you want to continue? [Y/n]: n
Here is the list of columns to choose from: ['DWUXZ', 'bKDoH', 'erLlI', 'QJAfR', 'dAfNn', 'kpwGt', 'fuDmY', 'WoTau', 'qrFaZ', 'ZGSkx']
Enter column names separated by comma (Hit enter to select all columns).
fda, dax
Do you want to continue? [Y/n]: y
Here is the list of columns to choose from: ['DWUXZ', 'bKDoH', 'erLlI', 'QJAfR', 'dAfNn', 'kpwGt', 'fuDmY', 'WoTau', 'qrFaZ', 'ZGSkx']
Enter column names separated by comma (Hit enter to select all columns).
Here is the list of columns to choose from: ['DWUXZ', 'bKDoH', 'erLlI', 'QJAfR', 'dAfNn', 'kpwGt', 'fuDmY', 'WoTau', 'qrFaZ', 'ZGSkx']
Enter column names separated by comma (Hit enter to select all columns).
OK. Selected all columns
column_names = ["DWUXZ", "bKDoH", "erLlI", "QJAfR", "dAfNn", "kpwGt", "fuDmY", "WoTau", "qrFaZ", "ZGSkx"]
def newfunc():
print (f"Here is the list of columns to choose from: {column_names}\n") //correction
args = input("Enter column names separated by comma (Hit enter to select all columns).\n").split(',')
userinputs_notfound = [] #This will hold the wrong entries entered by the user.
for arg in args:
if arg.replace(" ", "") not in column_names:
userinputs_notfound.append(arg.replace(" ", ""))
if len(userinputs_notfound) == 0:
pass
else:
if input("Do you want to continue? [Y/n]: ").lower() == 'y': //correction no need of while
newfunc()
newfunc() #Calling the function.
这个适用于 python 3.8+
# The list to choose from
col_names = ["DWUXZ", "bKDoH", "erLlI", "QJAfR", "dAfNn", "kpwGt", "fuDmY", "WoTau", "qrFaZ", "ZGSkx"]
def newFunc():
# Print all the available column names.
print("List of columns to choose from:\n", *col_names, sep = '\n')
# Filter out the missing names (if any) and ask for the prompt.
# The anonymous function inside lambda match against the empty
# string when the user chooses to select all.
while missing := list(filter(lambda name: name and name not in col_names,
input("\nEnter column names separated by comma (Hit enter to select all): ").split(','))):
print("Missing:", *missing, sep = '\n')
# Break the loop for any of the negetive response.
if input("\nDo you want to continue? ").lower() in ['n', "no", "nope", "nah"]:
break
# Implement here your logic when no missing is found.
# Call the function.
newFunc()
在赋值运算符的帮助下 := 我们只用了几行代码就做到了。