类问题 - 程序按预期运行，但 visual studio 代码突出显示语法错误

Question

我的程序按预期工作，当我执行从账户 1 到账户 2 的转账时，它输出正确的值。

但是，visual studio 代码在“self”下划了红色下划线（例如告诉我“'Account' 的实例没有 'filepath' 成员）

你能帮我理解我做错了什么吗？非常感谢！

下面是我的代码和输出，非常感谢！

class Account:
 
    def __init__(self):
        filepath=self.filepath  #self is underlined here
        with open(filepath,"r") as file:
            self.balance = int(file.read())
    
    def withdraw(self, amount):
        self.balance -= amount
    
    def deposit(self, amount):
        self.balance += amount
 
    def transfer(self, amount, receiver):
        self.newbalance = self.balance - amount
        receiver.newbalance = receiver.balance + amount
        print(self.accountname,"balance is",self.balance) #self is underlined here
        print(receiver.accountname,"balance is",receiver.balance)
        print(self.accountname,"transfering",amount,"to",receiver.accountname) #self is underlined here
        print(self.accountname, "new balance is",self.newbalance) #self is underlined here
        print(receiver.accountname, "new balance is",receiver.newbalance) 
 
class Louis(Account):
 
    accountname = "Louis" 
    filepath = "louis.txt"
 
class Romain(Account):
 
    accountname = "Romain"
    filepath = "romain.txt"
 
romain = Romain()
louis = Louis()
 
romain.transfer(99,louis)

输出

Romain balance is 2000
Louis balance is 1000
Romain transfering 99 to Louis
Romain new balance is 1901
Louis new balance is 1099

Answer 1

问题是你只在子class中设置了filepath。如果您尝试创建 Account 对象而不是 Louis 或 Romain，或者您使用另一个未设置 filepath 的子 class，您会得到一个错误。 VS Code 没有任何方式知道你从未这样做过，它只是自己分析 class。

Answer 2

我相信继承在这里导致了一些混乱。虽然 Louis 和 Roman 都初始化了 filepath，但帐户基础 class 从未初始化 filepath。 Visual studio 将此标记为语法错误，因为如果您已经初始化了一个 Account 实例，您的代码就会引发 AttributeError。例如：

class Account:    
     
    def __init__(self):    
        filepath=self.filepath  #self is underlined here    
        with open(filepath,"r") as file:    
            self.balance = int(file.read())    
        
    def withdraw(self, amount):    
        self.balance -= amount    
        
    def deposit(self, amount):    
        self.balance += amount    
     
    def transfer(self, amount, receiver):    
        self.newbalance = self.balance - amount    
        receiver.newbalance = receiver.balance + amount    
        print(self.accountname,"balance is",self.balance) #self is underlined here    
        print(receiver.accountname,"balance is",receiver.balance)    
        print(self.accountname,"transfering",amount,"to",receiver.accountname) #self is underlined here    
        print(self.accountname, "new balance is",self.newbalance) #self is underlined here    
        print(receiver.accountname, "new balance is",receiver.newbalance)     
     
class Louis(Account):    
     
    accountname = "Louis"     
    filepath = "louis.txt"    
     
class Romain(Account):    
     
    accountname = "Romain"    
    filepath = "romain.txt"    
     
romain = Romain()    
louis = Louis()    
     
romain.transfer(99,louis)    
    
account = Account()

输出

Romain balance is 2000
Louis balance is 1000
Romain transfering 99 to Louis
Romain new balance is 1901
Louis new balance is 1099
Traceback (most recent call last):
  File "/home/test.py", line 38, in <module>
    account = Account()
  File "/home/test.py", line 4, in __init__
    filepath=self.filepath  #self is underlined here
AttributeError: 'Account' object has no attribute 'filepath'

Answer 3

你的filepath是一个Class变量而不是实例变量

Louis 和 Romain 需要成为 Account

的实例

class Account:    
     
    def __init__(self, accountname, filepath):
        self.filepath = filepath
        self.accountname = accountname
        self.balance = 0
        with open(self.filepath,"r") as file:    
            self.balance = int(file.read())    
        
    def withdraw(self, amount):    
        self.balance -= amount    
        
    def deposit(self, amount):    
        self.balance += amount    
     
    def transfer(self, amount, receiver):    
        self.newbalance = self.balance - amount    
        receiver.newbalance = receiver.balance + amount    
        print(self.accountname,"balance is",self.balance)
        print(receiver.accountname,"balance is",receiver.balance)    
        print(self.accountname,"transfering",amount,"to",receiver.accountname)
        print(self.accountname, "new balance is",self.newbalance)
        print(receiver.accountname, "new balance is",receiver.newbalance)     
    
romain = Account("Romain", "romain.txt")
louis = Account("Louis", "louis.txt")

romain.transfer(99,louis)

类问题 - 程序按预期运行，但 visual studio 代码突出显示语法错误

Issue with Classes - Program works as intended, but visual studio code is highlighting syntax error

python

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类 问题 - 程序按预期运行，但 visual studio 代码突出显示语法错误

Issue with Classes - Program works as intended, but visual studio code is highlighting syntax error

python

visual-studio-code

syntax-highlighting

类问题 - 程序按预期运行，但 visual studio 代码突出显示语法错误