if __name__ == '__main__' 深入理解

name

—–首先，我们来看这个name 是当前的模块名，当模块被直接运行时模块名为 main ，如果当前模块不是直接运行时模块名就不是main，也就是当模块是被外部导入时，模块名不是main。在Python中，一个.py文件就是一个模块，一般情况下，模块的名字就是文件名(不包括扩展名.py)。全局变量name存放的就是模块的名字。

例子

—–该实例引用自以下链接以及知乎
https://link.zhihu.com/?target=http%3A//stackoverflow.com/questions/419163/what-does-if-name-main-do
作者：知乎用户
链接：https://www.zhihu.com/question/49136398/answer/114437881
来源：知乎

# file one.py
def func():
    print("func() in one.py")

print("top-level in one.py")

if __name__ == "__main__":
    print("one.py is being run directly")
else:
    print("one.py is being imported into another module")

# file two.py
import one

print("top-level in two.py")
one.func()

if __name__ == "__main__":
    print("two.py is being run directly")
else:
    print("two.py is being imported into another module")

结果

—–执行one.py得到
top-level in one.py
one.py is being run directly

—–执行two.py得到
top-level in one.py
one.py is being imported into another module
top-level in two.py
func() in one.py
two.py is being run directly

最后

—–自己在学习Python中，遇到的好的东西，理解比较深刻的东西，总结下写下来，分享给大家，对于原出处已经给予明确显示，如有侵权，请联系我删除。