if__name__==__main__:有什么作用

一个python的文件有两种使用的方法，第一是直接作为脚本执行，第二是在其他文件的python脚本中被import即调用（模块重用）执行。因此if name == 'main':的作用就是控制这两种情况执行代码的过程，在if name == 'main':下的代码只有在第一种情况下（即文件作为脚本直接执行）才会被执行，而import到其他脚本中是不会被执行的。

例子：

# file one.pydef 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.pyimport one        # start executing one.pyprint("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") 

当运行python one.py， 输出:

top-level in one.py
one.py is being run directly 

当运行python two.py, 输出:

top-level in one.py
one.py is being imported into another module
top-level in one.pyfunc() in one.py
two.py is being run directly 

以上就是if __name__ == __main__:有什么作用的详细内容，更多请关注Gxl网其它相关文章！

查看更多关于if__name__==__main__:有什么作用的详细内容...