Python - 类 - 自我未定义

Question

下面我尝试制作一个简单的 Keygen 作为第一个项目。在某处我收到错误 Self 尚未定义。

我猜这可能很容易

import random

class KeyGenerator():
def __init__(self):

    length = 0
    counter = 0
    key = []
    Letters = ['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z']



def KeyGen4(self):
    while self.counter != self.length:
        a = random.choice(self.Letters)
        print a #test
        r = (random.randint(0,1))
        print r #test
        if r == True:
            a = a.upper()
        else:
            pass
        self.key.append(a)
        self.counter += 1

    s = ''      
    self.key = s.join(key)
    print self.key
    return self.key

def start(self):
    selection = raw_input('[K]eygen4, [C]ustom length Keygen or [N]umbers? >')

    if selection == 'K' or 'k':
        length = 4
        keyGen4(self)

    elif selection == 'N' or 'n':
        KeyGenN(self)

    elif selection == 'C' or 'c':
        length = int(raw_input("Key Length: "))
    #KeyGen4(self) # Change later after creating method with more options

start(self) 

Answer 1

1. 您的缩进是错误的，但我认为这只是一个复制粘贴问题。

2. 这start(self)在底部没有意义，
   确实self是没有定义。你应该创建一个类的实例，然后调用它的start方法：

   KeyGenerator().start()
   
   # or 
   
   key_gen = KeyGenerator()
   key_gen.start()