Question

我的问题解释起来有点棘手。让我举个例子。我有以下类定义：

class Person(object):     
    def __init__(self, name):         
        self.name = name  

    def say(self, stuff):         
        return self.name + ' says: ' + stuff     
    def __str__(self):         
        return self.name  

class Lecturer(Person):     
    def lecture(self, stuff):         
        return 'I believe that ' + Person.say(self, stuff)  

class Professor(Lecturer): 
    def say(self, stuff): 
        return self.name + ' says: ' + self.lecture(stuff)

class ArrogantProfessor(Professor): 
    def say(self, stuff): 
        return self.name + ' says: It is obvious that ' + Lecturer.lecture(self, stuff)

    def lecture(self, stuff):
        return 'It is obvious that ' + Lecturer.lecture(self, stuff)

现在我想修改除ArrogantProfessor类之外的任何类，以便我得到以下内容：

>>> pe.say('the sky is blue')
Prof. eric says: I believe that eric says: the sky is blue 

>>> ae.say('the sky is blue')
Prof. eric says: It is obvious that I believe that eric says: the sky is blue

我应该补充一点，pe = Professor('eric')和ae = ArrogantProfessor('eric') 更改基本上是在开头添加Prof.标题，因此它对所有方法都是通用的。因此我尝试添加类似＆＃34; title＆＃34;到self.name课程__init__方法中的Person(object) - 但没有成功。有没有人有更好的主意谢谢！

Answer 1

class Professor(Person):
    def __init__(self, name):
        self.name = 'Prof. ' + name

按照要求回答你的问题

可能你想要这样的东西：

Professor

然后只有__init__（和它的子类）才会继承'教授'。标题。

此问题的关键是覆盖function chunk(\Generator $generator, $n) { for ($i = 0; $generator->valid() && $i < $n; $generator->next(), ++$i) { yield $generator->current(); } } function foo() { for ($i = 0; $i < 11; ++$i) { yield $i; } } for ($gen = foo(); $gen->valid();) { $chunk = []; foreach (chunk($gen, 3) as $value) { $chunk[] = $value; } print json_encode($chunk) . "\n"; }

Answer 2

如果您需要方法ArrogantProfessor.say()继承方法Professor.say()，稍微改变其输出，则必须更改两个类中的方法say()。

在Professor.say()中，您可以添加标题“教授”，在ArrogantProfessor.say()中，您必须通过say()调用父方法super()。

class Professor(Lecturer):
    def say(self, stuff):
        return 'Prof. ' + self.name + ' says: ' + self.lecture(stuff)

class ArrogantProfessor(Professor):
    def say(self, stuff):
        return super(ArrogantProfessor, self).say(stuff)
    def lecture(self, stuff):
        return 'It is obvious that ' + Lecturer.lecture(self, stuff)

我建议您查看有关继承的文档和super()。

如Ben Jarrett所述，您也可以修改Professor.\__init__()方法而不是上述方法，但在这种情况下，您的输出将变为：

Prof. eric says: I believe that Prof. eric says: the sky is blue
Prof. eric says: It is obvious that I believe that Prof. eric says: the sky is blue

如何修改全局使用的类

2 个答案: