Question

我正在创建一个类，在初始化它时，我正在调用（多进程）它的函数。当我从相同的 .py 文件创建此类时，一切正常。但是，当我从另一个 .py 文件初始化此类时 - 它失败并抛出错误...为什么？

MyDummyClass.py：

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example.py：

import multiprocessing
class MyDummyClass:            
    def __init__(self):        

        print("I am in '__init__()'")

        if __name__ == 'MyDummyClass':

            p = multiprocessing.Process(target=self.foo())
            p.start()


    def foo(self):
        print("Hello from foo()")

当我运行example.py时，我收到此错误：

from MyDummyClass import MyDummyClass 
dummy = MyDummyClass()

我无法理解（而不是来自其他帖子）如何修复它。

非常感谢你的帮助!!

Answer 1

这与python实际执行脚本的方式有关。它抛出的错误实际上表明，当python尚未准备就绪时，您正在尝试启动新进程。这是因为您在主脚本中调用dummy = MyDummyClass()而没有给python完全初始化的机会。如果您改为example.py，请执行以下操作：

from MyDummyClass import MyDummyClass 
if __name__ == "__main__":
    dummy = MyDummyClass()

这将产生您想要的输出：

C:\Python Scripts>python example.py
I am in '__init__()'
Hello from foo()

if __name__ == "__main__"块告诉python＆＃34;只有在脚本作为主脚本运行时才执行此操作（即python example.py），这将迫使python在运行之前正确初始化所有内容那个街区。

道歉，如果这个答案没有足够描述python后端正在进行的初始化过程中发生了什么，我自己也不了解它：）

无法从另一个python .py文件运行进程

1 个答案: