TypeError：__ init __（）只需2个参数（给定1个）

Question

我不明白为什么我收到以下错误，并希望得到一些建议。感谢。

错误：

Traceback (most recent call last):
  File "test.py", line 5, in <module>
    ciphertext = md.encrypt(plaintext)
  File "/Volumes/Mac/Computer/Programming/Cryptography/crypto.py", line 87, in encrypt
    ciphertext = Text()
TypeError: __init__() takes exactly 2 arguments (1 given)

代码：

import crypto

plaintext = crypto.Text('plaintext.txt')
md = crypto.MonomeDinome('fred', 'wilma')
ciphertext = md.encrypt(plaintext)
print ciphertext

Crypto.py包含以下代码：

class Text:
    def __init__(self, filename):
        self.load(filename)

    def load(self, filename):
        fp = open(filename, "r")
        self.rawtext = fp.read()
        fp.close
        self.text = self.convert(self.rawtext)

    def convert(self, txt):
        rval = ""
        for c in txt.upper():
            if c.isalpha():
                rval += c
        return rval

    def set(self, lst):
        self.text = "".join(lst)

    def get(self):
        return self.text

    def __str__(self):
        rval = ""
        pos = 0
        for c in self.text:
            rval += c
            pos += 1
            if pos % 60 == 0:
                rval += '\n'
            elif pos % 5 == 0:
                rval += " "
        return rval

class MonomeDinome:
    def __init__(self, dkw, lkw):
        self.digitsKey = self.digitsScramble(dkw)
        self.lettersKey = self.lettersScramble(lkw)

    def digitsScramble(self, dkw):
        dkl = list((dkw.upper() + "ZZZZZZZZZZ")[0:10])

        for i in "0123456789":
            pos = self.findLowestLetter(dkl)
            if pos != -1:
                dkl[pos] = i

        return "".join(dkl)

    def findLowestLetter(self, lst):
        pos = -1
        lowest = ''

        for i in range(len(lst)):
            if lst[i].isalpha():
                if (lowest == '') or (lst[i] < lowest):
                    lowest = lst[i]
                    pos = i
        return pos

    def lettersScramble(self, lkw):
        rlist = []
        for a in lkw.upper():
            if a == "W":
                a = "V"
            if a == "J":
                a = "I"
            if not a in rlist:
                rlist.append(a)

        for a in "ABCDEFGHIKLMNOPQRSTUVXYZ":
            if not a in rlist:
                rlist.append(a)

        return "".join(rlist)

    def __str__(self):
        return "digitsKey = " + self.digitsKey + "\n" + \
                "lettersKey = " + self.lettersKey

    def encrypt(self, plaintext):
        rlist = []
        for char in plaintext.get():
            rlist.append(char)
        ciphertext = Text()
        ciphertext.set(rlist)
        return ciphertext

Answer 1

构造函数的filename参数不是可选的，因此在encrypt中失败：ciphertext = Text()。它必须是... = Text(some_filename)

Answer 2

我认为您希望Text采用0或1选项参数。

class Text:
    def __init__(self, filename=None):
        if filename is not None:
            self.load(filename)

---

我相信

    ciphertext = Text()

是有道理的。

    ciphertext.set(rlist)

是设置ciphertext.text的另一种方式，而不是调用load方法。

---

顺便说一下，load：

也有错误

def load(self, filename):
    ...
    fp.close()   # <--- You need parentheses or else the closed method is not called

您可以使用with语法来避免错误：

def load(self, filename):
    with open(filename, "r") as fp:
        self.rawtext = fp.read()
    self.text = self.convert(self.rawtext)

使用with语法，当Python离开fp套件时，文件句柄with会自动关闭。