类型错误：“builtin_function_or_method”对象不支持项目分配

Question

我有这样的错误，当我尝试运行我的脚本：

Traceback (most recent call last): 
    File "<pyshell#6>", line 1, in <module> 
    converter() 
    File "C:\Users\Joan\Documents\School\Computing\Coursework\A453 - Python\Currency Converter.py", line 19, in converter 
    exchange(currencyList) 
    File "C:\Users\Joan\Documents\School\Computing\Coursework\A453 - Python\Currency Converter.py", line 33, in exchange 
    crntItem = currencyList.index[crntCurrency] =+ 1 
TypeError: 'builtin_function_or_method' object does not support item assignment 

这里是我的代码，一个未完成的货币换算：

# Global ist 
currencyList = ["Pound Sterling", 1, "Euro", 1.22, "US Dollar", 1.67, "Japanese Yen", 169.9480] 



################################# 
# A program to convert currency # 
# Main function     # 
################################# 
def converter(): 
    currencyList = ["Pound Sterling", 1, "Euro", 1.22, "US Dollar", 1.67, "Japanese Yen", 169.9480] 
    print("1) Enter an amount to be exchanged.") 
    print("2) Change exchange rates.") 
    choice=0 
    while choice==0: 
     selected=int(input("Please select an option: ")) 
     if selected == 1: 
      choice = 1 
      exchange(currencyList) 




################################# 
# Giving exchanged rate   # 
################################# 

def exchange(currencyList): 
    crntAmnt = int(input("Please enter the amount of money to convert: ")) 
    crntCurrency = ("Please enter the current currency: ") 
    newCurrency = ("Please enter the currency you would like to convert to: ") 
    listLength = len(currencyList) 
    crntItem = currencyList.index[crntCurrency] =+ 1 
    print(crntItem) 
    newItem = currencyList.index[newCurrency] =+ 1 
    print(newItem) 

我试图设置一个主要功能作为菜单，然后调用其他子功能来完成相关的选择。我希望得到一些建议，说明这是否是一种好的方法，因为我看到我的老师做了类似的事情，我应该把它写进'if'陈述等。

这是一个好的，正确的方法编码？

Answer 1

currencyList.index是方法的参考;索引列表，删除.index部分：

crntItem = currencyList[crntCurrency] 
print(crntItem) 
newItem = currencyList[newCurrency] 

我嫌疑你正在努力寻找列表中的crntCurrency指标，再加入1找到替代的价值：

crntItem = currencyList[currencyList.index(crntCurrency) + 1] 

和

newItem = currencyList[currencyList.index(newCurrency) + 1] 

但也许你应该在这里使用字典来代替：

currencies = {"Pound Sterling": 1, "Euro": 1.22, "US Dollar": 1.67, "Japanese Yen": 169.9480} 

此货币名称映射到一个号，所以现在你可以只是仰望货币，而无需摆弄指数：

crntItem = currencies[crntCurrency] 

哦，你忘了采取实际用户输入;当请求货币转换时添加input()呼叫：

crntCurrency = input("Please enter the current currency: ") 
newCurrency = input("Please enter the currency you would like to convert to: ")