有关类及其方法的问题

Question

我目前正在尝试编写一个ircbot并被卡住。 如您所见，我为ircBot类connect方法定义了一个方法，该方法创建了一个套接字对象。 我想在sendCmd方法中使用此对象，这可能吗？

我一直在寻找google和stackoverflow，但无法找到解决方案（可能是因为我是Python的新手）。 任何提示表示赞赏！

import socket
import sys
import os

class ircBot:

    def sendCmd(self, cmd):
        SEND_TEXT_ON_OPEN_SOCKET

    def connect(self, server, port):

        s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        c = s.connect_ex((server, port))

        if c == 111:
            print("Error: " + os.strerror(c))
            sys.exit(1)

            print("Making connection to " + server + "\n")

问候，

大卫

Answer 1

技巧是方法的第一个参数，通常在Python中称为self 。 调用方法时，将自动传递此参数。

它是该类的实例-因此，如果执行ircbot.sendCmd(cmd) ，则sendCmd ircbot用作self ，因此如果需要，可以将其自身用作self.sendCmd 。

您可以将属性添加到self ，并将其添加到实例-这意味着connect对self所做的操作， sendCmd也会看到。

import socket
import sys
import os

class IrcBot: # You should consider doing 'class IrcBot(object):'
              # if you're on Python 2, so it's a new-style class
    def sendCmd(self, cmd):
        # use self.s here
        SEND_TEXT_ON_OPEN_SOCKET

    def connect(self, server, port):

        self.s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        c = self.s.connect_ex((server, port))

        if c == 111: # is this the only return code that matters?
                     # I don't know, you might want to check for others
            print("Error: " + os.strerror(c))
            sys.exit(1)

            print("Making connection to " + server + "\n")

ircbot = IrcBot()
ircbot.connect('localhost', 6667)
ircbot.sendCmd('yourcmd')

Answer 2

您需要将其分配给可以在connect外部访问的变量。 通常，这是通过创建称为成员级别变量的东西来完成的：

class ircBot:

    def sendCmd(self, cmd):
        # SEND_TEXT_ON_OPEN_SOCKET
        s.doSomething()

    def connect(self, server, port):

        s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        c = s.connect_ex((server, port))

        if c == 111:
            print("Error: " + os.strerror(c))
            # this should probably simply throw an exception. No need to take teh
            # whole system down on socket connection failure.
            sys.exit(1)
        self.s = s
        # I moved this up a level because you could never get to it in the 
        # if statement -- sys.exit leaves the application!
        print("Making connection to " + server + "\n")

Answer 3

import socket
import sys
import os

class ircBot:

    def sendCmd(self, cmd):
        if self.s is None:
           raise "Not connected to a server"
        self.s.send(cmd)

    def connect(self, server, port):

        self.s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        c = self.s.connect_ex((server, port))

        if c == 111:
            print("Error: " + os.strerror(c))
            sys.exit(1)

            print("Making connection to " + server + "\n")