對象在類之外沒有屬性

Question

你好，我正在做一個項目，在創建一個類后，我無法訪問外部的方法以使功能正常工作。 我想使用我班級中的方法來添加或刪除余額和顯示。

任何幫助都會很棒

代碼：

class BankAccount:
    def __init__(self, full_name, account_number, routing_number, balance):
        self.full_name = full_name
        self.account_number = account_number
        self.routing_number = routing_number
        self.balance = balance

        def deposit(amount):
            self.balance += amount
            print("\n Amount Deposited:", amount)

        # Function to withdraw the amount
        def withdraw(self):
            amount = float((input("Enter a amount")))
            if self.balance >= amount:
                self.balance -= amount
                print("\n You Withdrew", amount)
            else:
                print("\n Insufficient funds.")
                self.balance - 10
        # Function to display the amount

        def display_balance(self):
            print("\n You have ", self.balance)

        def add_interest(balance):
            interest = balance * 0.00083

        def print_receipt():
            print(full_name)
            print("Account Number: " + account_number)
            print("routing number: " + routing_number)
            print("balance:" + balance)


# creating an object of class
s = BankAccount("Bob", 00000, 0000, 1)

# Calling functions with that class object
s.withdraw(22)
s.display()
# Calling functions with that class object

Answer 1

您在類方法中缺少對 self 的引用。 嘗試這個：

class BankAccount:
    def __init__(self, full_name, account_number, routing_number, balance):
        self.full_name = full_name
        self.account_number = account_number
        self.routing_number = routing_number
        self.balance = balance

        def deposit(self, amount):
            self.balance += amount
            print("\n Amount Deposited:", amount)

        # Function to withdraw the amount
        def withdraw(self):
            amount = float((input("Enter a amount")))
            if self.balance >= amount:
                self.balance -= amount
                print("\n You Withdrew", amount)
            else:
                print("\n Insufficient funds.")
                self.balance - 10
        # Function to display the amount

        def display_balance(self):
            print("\n You have ", self.balance)

        def add_interest(self, balance):
            interest = self.balance * 0.00083

        def print_receipt(self):
            print(self.full_name)
            print("Account Number: " + self.account_number)
            print("routing number: " + self.routing_number)
            print("balance:" + self.balance)

此外，您正在調用類中未定義的display()函數。 我相信你的意思是使用display_balance() 。

最后，當您調用withdraw()函數時，您將輸入一個值作為該函數的參數，但該函數並非設計為接受任何參數。 您編寫它的方式要求用戶在命令行上輸入。 如果你希望它接受參數，你可以像這樣重新定義它：

# Function to withdraw the amount
def withdraw(self, amount):
    if self.balance >= amount:
        self.balance -= amount
        print("\n You Withdrew", amount)
    else:
        print("\n Insufficient funds.")
        self.balance - 10