Question

我在这里创建了一个模块。

class Employee:
    def __init__(self):
        self.name = input("Enter your name: ")
        self.account_number = int(input("Enter your account number: "))
    def withdraw(self):   # it receives values from for
        if withdraw1 > current_balance:
            print ("You have entered a wrong number: ")
        else:
            print ("The current balance is: ", current_balance - withdraw1)

import TASK2 # I am importing the module I created 

c = TASK2.Employee()
def for(self):
    c.withdraw1 = int(input("enter number: "))
    c.current_balance = int(input("Enter the current balance: "))
d = method(c.withdraw) # here I am trying to pass the values to withdraw
print (d)

我得到的问题是，尽管它要求输入值而不是给我答案，但它给我的答案是“无”。

Answer 1

这是我对您的代码的看法。

# TASK2.py
class Employee:
    def __init__(self):
        self.name = input("Enter your name: ")
        self.account_number = int(input("Enter your account number: "))

        # make sure you initialise your member variables!
        self.withdraw_val = 0            # withdraw1 is ambiguous, so I use withdraw_val instead
        self.current_balance = 0

    # receives values from for ### no it doesn't, right now, it GIVES values TO your "for" function
    def withdraw(self):   
        if self.withdraw_val > self.current_balance:   # remember to use "self." to
                                                       # access members within the class
            print ("You have entered a wrong number: ")
        else:
            # again, remember "self."
            print ("The current balance is: ", self.current_balance - self.withdraw_val)

# TASK2sub.py

import TASK2

c = TASK2.Employee()

def for_employee(employee): # (1) don't use "self" outside a class
                            # it's contextually unconventional
                            # (2) "for" is a keyword in Python, don't use it for naming
                            # variables/functions, it'll mess things up

    employee.withdraw_val = int(input("Enter value to withdraw: "))
    employee.current_balance = int(input("Enter the current balance: "))

    return employee.withdraw_val  # not entirely sure what you want to return
                              # but you should definitely return something
                              # if you're going to assign it to some variable


d = for_employee(c.withdraw()) # "for_employee" function needs a return statement
                               # ".withdraw()" method should also require a return statement
print(d)

注意：从现在开始，我将把您原来的for函数称为for_employee。另外请注意，我对您要完成的任务仍然不甚了解，并且很可能有一个更合适的名称。

由于原始for_employee函数未返回任何内容，因此默认情况下它将返回None。（这说明了您看到的输出。）

我认为您误会了函数的总体工作方式。例如，

d = for_employee(c.withdraw())
print(d)

您对.withdraw()方法的评论不正确。

“它从中接收值”

更准确地说，将首先计算c.withdraw()，然后将返回的所有内容作为参数传递到for_employee函数中。 withdraw方法不是“从中接收值”，而是“将值提供给” for_employee函数。

更合理的选择

c.withdraw()         # on a line by itself, since it doesn't return anything
d = for_employee(c)  # pass the entire object, since you'll be using self.withdraw_val and whatnot

print(d)

另一个问题是常规命名。这是我在定义名为for

的函数时从IDLE（使用Python 3.7）获得的结果

>>> def for(a): return a
SyntaxError: invalid syntax

同样，

for 是Python中的关键字，请勿使用它来命名变量，函数或类。

使用self时，情况不太严重（但我可以看到它使您感到困惑）。 self更是类方法中使用的约定。但是for_employee 不是一个类方法。因此，按照惯例，该参数不应命名为self。

（我发现代码是意大利式的，如果您通过将for_employee方法移到类本身来重构代码，可能会有所帮助。然后使用{ {1}}。）

它要求给出值，而不是给出答案。它没有给我

1 个答案: