在函数python中重新设置全局数组中的值。

I am coding in python and ....

我在python和....编码

I have a quick question. I am trying to reset the values of a global array by calling a certain function but am having difficulty. Here is my code at the moment:

我有个问题。我试图通过调用某个函数来重置全局数组的值，但遇到了困难。以下是我目前的密码:

CHOICES = (('1', 'First'), ('2', 'Second'))

def set_choices():
    global CHOICES
    CHOICES = (('3', 'Third'), ('4', 'Fourth'))

Essentially what I want to do is reset the array CHOICES by calling the function from some other function. Is there a way to do that?

本质上，我要做的是通过从其他函数调用函数来重置数组选项。有办法做到吗?

Thanks!

谢谢!

2 个解决方案

#1

myObject = [('1', 'First'), ('2', 'Second')] 
CHOICES = set(myObject)

def set_choices():
    global CHOICES
    CHOICES.clear() # Remove the element from set CHOICES
    # Do some of your changes here
    anotherObject = [('3', 'Third'), ('4', 'Fourth')]
    CHOICES[:] = set(anotherObject)


print(CHOICES) # Before calling set_choices
set_choices()
print(CHOICES) # After you calling set_choices

I think this will work. But I don't know if using set and tuple is a good idea, I personally would suggestion you to use list of list instead. Are there particular reason to use a set instead of other options?

我想这行得通。但是我不知道用set和tuple是不是一个好主意，我个人建议你用list代替。是否有特别的理由使用集合而不是其他选项?

Output:

输出:

{('2', 'Second'), ('1', 'First')}
{('4', 'Fourth'), ('3', 'Third')}

Respond to your comment to use list:

回复你的评论使用列表:

CHOICES = [['1', 'First'], ['2', 'Second']]

def set_choices():
    # Changed since the comment of another member aaronasterling
    # Removed the use of global
    CHOICES[:] = [['3', 'Third'], ['4', 'Fourth']]

print(CHOICES)
set_choices()
print(CHOICES)

Output:

输出:

[['1', 'First'], ['2', 'Second']]
[['3', 'Third'], ['4', 'Fourth']]

To learn more about slice assignment, check out this SO question & answer.

要了解更多关于片赋值的信息，请查看“所以问题和答案”。

#2

If you want to do this with a list then there's no need for the global keyword.

如果您想要使用列表来完成此操作，那么不需要使用全局关键字。

CHOICES = [('1', 'First'), ('2', 'Second')

def set_choices():
    CHOICES[:] = (('3', 'Third'), ('4', 'Fourth'))

This will replace the content of the list without changing the reference. It works by slice assignment. The CHOICES[:] references a slice of the whole list.

这将在不更改引用的情况下替换列表的内容。它的工作原理是切片作业。选项[:]引用整个列表的一部分。