在 Python 中创建菜单
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Creating a Menu in Python
提问by Hyman
I'm working on making a menu in python that needs to:
我正在用 python 制作一个菜单，它需要：
- Print out a menu with numbered options
- Let the user enter a numbered option
- Depending on the option number the user picks, run a function specific to that action. For now, your function can just print out that it's being run.
- If the user enters in something invalid, it tells the user they did so, and re-display the menu
- use a dictionary to store menu options, with the number of the option as the key, and the text to display for that option as the value.
- The entire menu system should run inside a loop and keep allowing the user to make choices until they select exit/quit, at which point your program can end.
- 打印带有编号选项的菜单
- 让用户输入编号选项
- 根据用户选择的选项编号，运行特定于该操作的函数。现在，您的函数可以打印出它正在运行。
- 如果用户输入了无效的内容，它会告诉用户他们这样做了，并重新显示菜单
- 使用字典来存储菜单选项，以选项编号作为键，以该选项显示的文本作为值。
- 整个菜单系统应该在循环内运行，并继续允许用户进行选择，直到他们选择退出/退出，此时您的程序可以结束。
I'm new to Python, and I can't figure out what I did wrong with the code.
我是 Python 的新手，我无法弄清楚我在代码中做错了什么。
So far this is my code:
到目前为止，这是我的代码：
ans=True
while ans:
print (""""
1.Add a Student
2.Delete a Student
3.Look Up Student Record
4.Exit/Quit
"""")
ans=input("What would you like to do?"
if ans=="1":
print("\nStudent Added")
elif ans=="2":
print("\n Student Deleted")
elif ans=="3":
print("\n Student Record Found")
elif ans=="4":
print("\n Goodbye")
elif ans !="":
print("\n Not Valid Choice Try again")
ANSWERED
回答
This is what he wanted apparently:
这显然是他想要的：
menu = {}
menu['1']="Add Student."
menu['2']="Delete Student."
menu['3']="Find Student"
menu['4']="Exit"
while True:
options=menu.keys()
options.sort()
for entry in options:
print entry, menu[entry]
selection=raw_input("Please Select:")
if selection =='1':
print "add"
elif selection == '2':
print "delete"
elif selection == '3':
print "find"
elif selection == '4':
break
else:
print "Unknown Option Selected!"
回答by ChrisProsser
There were just a couple of minor amendments required:
只需要进行一些小的修改：
ans=True
while ans:
print ("""
1.Add a Student
2.Delete a Student
3.Look Up Student Record
4.Exit/Quit
""")
ans=raw_input("What would you like to do? ")
if ans=="1":
print("\n Student Added")
elif ans=="2":
print("\n Student Deleted")
elif ans=="3":
print("\n Student Record Found")
elif ans=="4":
print("\n Goodbye")
elif ans !="":
print("\n Not Valid Choice Try again")
I have changed the four quotes to three (this is the number required for multiline quotes), added a closing bracket after "What would you like to do? "and changed input to raw_input.
我已将四个引号更改为三个（这是多行引号所需的数字），在后面添加了一个右括号"What would you like to do? "并将输入更改为 raw_input。
回答by jramirez
This should do it. You were missing a )and you only need """not 4 of them. Also you don't need a elif at the end.
这应该做。你错过了一个)，你只需要其中的"""4 个。最后你也不需要 elif 。
ans=True
while ans:
print("""
1.Add a Student
2.Delete a Student
3.Look Up Student Record
4.Exit/Quit
""")
ans=raw_input("What would you like to do? ")
if ans=="1":
print("\nStudent Added")
elif ans=="2":
print("\n Student Deleted")
elif ans=="3":
print("\n Student Record Found")
elif ans=="4":
print("\n Goodbye")
ans = None
else:
print("\n Not Valid Choice Try again")
回答by Joran Beasley
def my_add_fn():
print "SUM:%s"%sum(map(int,raw_input("Enter 2 numbers seperated by a space").split()))
def my_quit_fn():
raise SystemExit
def invalid():
print "INVALID CHOICE!"
menu = {"1":("Sum",my_add_fn),
"2":("Quit",my_quit_fn)
}
for key in sorted(menu.keys()):
print key+":" + menu[key][0]
ans = raw_input("Make A Choice")
menu.get(ans,[None,invalid])[1]()
回答by JFA
It looks like you've just finished step 3. Instead of running a function, you just print out a statement. A function is defined in the following way:
看起来您刚刚完成了第 3 步。您只需打印出一条语句，而不是运行函数。函数定义如下：
def addstudent():
print("Student Added.")
then called by writing addstudent().
然后通过写作调用addstudent()。
I would recommend using a whileloop for your input. You can define the menu option outside the loop, put the print statement inside the loop, and do while(#valid option is not picked), then put the if statements after the while. Or you can do a whileloop and continuethe loop if a valid option is not selected.
我建议while为您的输入使用循环。您可以在循环外定义菜单选项，将打印语句放在循环内，然后 do while(#valid option is not picked)，然后将 if 语句放在 while 之后。或者，如果未选择有效选项，您可以执行while循环和continue循环。
Additionally, a dictionary is defined in the following way:
此外，字典的定义方式如下：
my_dict = {key:definition,...}
