Python UnBoundLocalError：分配前引用了局部变量 [计数器]
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UnBoundLocalError: Local Variable Referenced Before Assignment [Counter]
提问by Justin
I'm new to Python and I've never learned any other programming language. I seem to be getting this error and I've read other posts but they say to put global before [dollars = 0] which produces a syntax error because it doesn't allow the [= 0]. I'm using the [dollars] as a counter so I can keep track of what I add to it and display it back when needed. Could someone help me? Thanks.
我是 Python 新手，从未学过任何其他编程语言。我似乎遇到了这个错误，我已经阅读了其他帖子，但他们说将 global 放在 [dollars = 0] 之前，这会产生语法错误，因为它不允许 [= 0]。我使用 [dollars] 作为计数器，这样我就可以跟踪我添加的内容并在需要时显示回来。有人可以帮助我吗？谢谢。
<>Code<>
<>代码<>
dollars = 0
def sol():
print('Search or Leave?')
sol = input()
if sol == 'Search':
search()
if sol == 'Leave':
leave()
def search():
print('You gain 5 bucks')
dollars = dollars + 5
shop()
def leave():
shop()
def shop():
shop = input()
if shop == 'Shortsword':
if money < 4:
print('I\'m sorry, but you don\'t have enough dollars to buy that item.')
shop1()
if money > 4:
print('Item purchased!')
print('You now have ' + dollars + ' dollars.')
sol()
<>Traceback<>
<>追溯<>
Traceback (most recent call last):
File "C:/Users/justin/Python/Programs I Made/Current/Testing.py", line 29, in <module>
sol()
File "C:/Users/justin/Python/Programs I Made/Current/Testing.py", line 7, in sol
search()
File "C:/Users/justin/Python/Programs I Made/Current/Testing.py", line 13, in search
dollars = dollars + 5
UnboundLocalError: local variable 'dollars' referenced before assignment
采纳答案by Sukrit Kalra
You need to add global dollars, like follows
您需要添加global dollars，如下所示
def search():
global dollars
print('You gain 5 bucks')
dollars = dollars + 5
shop()
Everytime you want to change a globalvariable inside a function, you need to add this statement, you can just access the dollarvariable without the globalstatement though,
每次要更改global函数内部的变量时，都需要添加此语句，但dollar无需该global语句即可访问该变量，
def shop():
global dollars
shop = input("Enter something: ")
if shop == 'Shortsword':
if dollars < 4: # Were you looking for dollars?
print('I\'m sorry, but you don\'t have enough dollars to buy that item.')
shop1()
if dollars > 4:
print('Item purchased!')
dollars -= someNumber # Change Number here
print('You now have ' + dollars + ' dollars.')
You also need to reduce the dollars, when you shop for something!
当您购物时，您还需要减少美元！
P.S - I hope you're using Python 3, you'll need to use raw_inputinstead.
PS - 我希望你使用的是 Python 3，你需要使用它raw_input。
回答by Daniel Roseman
You need to put global dollars, on a line on its own, inside any function where you change the value of dollars. In the code you've shown that is only in search(), although I assume you'll also want to do it inside shop()to subtract the value of the item you buy...
您需要将 单独global dollars放在一行中，放在您更改美元价值的任何函数中。在您显示的代码中，它仅在 中search()，尽管我假设您还想在内部进行shop()以减去您购买的物品的价值...
