Question

我正在编写一个有趣的Python程序但是试图从另一个文件中的类导入函数时遇到困难。这是我的代码：

#jurassic park mainframe

from random import randint
from sys import exit
from comm_system import Comm_system #the file i want to import from



class Jpark_mainframe(object):
    def mainframe_home(self):
    print "=====Welcome to the Jurassic Park Mainframe====="
    print "==========Security Administration==============="
    print "===========Communications Systems==============="
    print "===============System Settings=================="
    print "===================Quit========================="

    prompt = raw_input("What would you like to do? ")

    while prompt != "Quit":

        if prompt == "Security Administration":
            print "Please enter the 5-digit passcode:"
            security_passcode = "%d%d%d%d%d" % (2, 0, 1, 2, randint(1, 2))
            security_guess = raw_input(": ")
            security_guesses = 0

            while security_guess != security_passcode and security_guesses < 7:
                print "Incorrect. Please enter the security passcode."
                security_guesses += 1
                security_guess = raw_input(": ")

                if security_guess == security_passcode:
                    print "=========Security Administration======="
                    print "Area 1 Fences: Off"
                    print "Area 2 Fences: On"
                    print "Area 3 Fences: Off"
                    print "Velociraptor Compound: Off"
                    print "Lobby Security System: Off"
                    print "Entrance Facility System: Off"
                    print "To enable all systems, enter 'On'"


                    enable_security = raw_input(": ")

                    if enable_security == "On":
                        print "Systems Online."


        if prompt == "System Settings":
            print "You do not have access to system settings."
            exit(0)


        if prompt == "Communications Systems":
            print "===========Communications Systems==========="
            print "error: 'comm_link' missing in directories"
            exit(0)
            return Comm_system.run #this is where I want to return the 
                                                   #the other file

the_game = jpark_mainframe()
the_game.mainframe_home()

我想从另一个文件中的类返回一个名为run()的函数。当我导入文件时，它首先运行其中包含run()的类，然后继续运行原始代码。为什么会这样？

以下是comm_system的代码：

#communication systems


from sys import exit

class Comm_system(object):
def run(self):

    comm_directory = ["net_link", "tsfa_run", "j_link"]
    print "When the system rebooted, some files necessary for"
    print "communicating with the mainland got lost in the directory."
    print "The files were poorly labeled as a result of sloppy"
    print "programming on the staff's part. You must locate the"
    print "the file and contact the rescue team before the dinosaurs"
    print "surround the visitor's center. You were also notified the"
    print "generators were shorting out, and the mainframe will lose"
    print "power at any moment. Which directory will you search in?"
    print "you don't have much time! Option 1: cd /comm_sys/file"
    print "Option 2: cd /comm_sys/dis"
    print "Option 3: cd /comm_sys/comm"

    dir_choice = raw_input("jpark_edwin$ ")

    if dir_choice == "/comm_sys/file" or dir_choice == "/comm_sys/dis":
        print "misc.txt" 
        print "You couldn't locate the file!"
        print "The system lost power and your computer shut down on you!"
        print "You will not be able to reach the mainland until the system"
        print "comes back online, and it will be too late by then."
        return 'death'

    if dir_choice == "/comm_sys/comm":
        comm_directory.append("comm_link")
        print comm_directory
        print "You found the right file and activated it!"
        print "Just in time too, because the computers shut down on you."
        print "The phonelines are radios are still online."
        print "You and the other survivors quickly call the mainlane"
        print "and help is on the way. You all run to the roof and wait"
        print "until the helocopter picks you up. You win!"
a_game = Comm_system()
a_game.run()

Answer 1

from otherfile import TheClass
theclass = TheClass()
# if you want to return the output of run
return theclass.run()  
# if you want to return run itself to be used later
return theclass.run

将通讯系统的结尾更改为：

if __name__ == '__main__':
    a_game = Comm_system()
    a_game.run()

这些行总是运行导致它在导入和执行时运行。

Answer 2

如果像我一样，你想制作一个功能包或人们可以下载的东西，那么它非常简单。只需在python文件中编写您的函数，并将其保存为您在PYTHON PIRTHON目录中的名称。现在，在您要使用它的脚本中，键入：

from FILE NAME import FUNCTION NAME

注意 - 大写字母的部分是您键入文件名和函数名的位置。

现在你只是使用你的功能，但它应该是。

示例：

FUNCTION SCRIPT - 在C：\ Python27中保存为function_choose.py

def choose(a):
  from random import randint
  b = randint(0, len(a) - 1)
  c = a[b]
  return(c)

脚本使用功能 - 保存在

的任何地方

from function_choose import choose
list_a = ["dog", "cat", "chicken"]
print(choose(list_a))

输出将是狗，猫或鸡

希望这有帮助，现在你可以创建下载功能包了！

--------------------------------这是为Python 2.7 ---------- ---------------------------

Answer 3

首先，您需要确保两个文件是否在同一个工作目录中。接下来，您可以导入整个文件。例如，

import myClass

或者您可以从文件中导入整个类和整个函数。例如，

from myClass import

最后，您需要从原始文件创建该类的实例并调用实例对象。

Answer 4

如果您包含不起作用的代码（来自“其他”文件），这确实会有所帮助，但我怀疑您可以通过'eval'功能的健康剂量来做您想做的事。

例如：

def run():
    print "this does nothing"

def chooser():
    return "run"

def main():
    '''works just like:
    run()'''
    eval(chooser())()

选择器返回要执行的函数的名称，然后eval将字符串转换为实际执行的代码，括号结束函数调用。

Answer 5

您可以使用以下语法 -

from FolderName.FileName import Classname

从另一个文件中的类导入函数？

5 个答案: