Python功能之反射
- 2020 年 1 月 14 日
- 笔记
有如下文件:
index.py
#!/usr/bin/env python # -*- coding:utf-8 -*- __author__ = 'ryan' """ import home print 'oldboy....' url=raw_input('url:') if url == 'home/dev': ret = home.dev() print ret if url =='/home/index': ret = home.index() print ret if url =='/home/user': ret = home.user print ret if url == '/home/passwd': ret = home.passwd print ret else: print '404' """ #getattr、setattr、delattr、 hasattr #找到home文件，将内容加载到内存，然后getattr、setattr、delattr、 hasattr 对home中断函数进行操作 #由于函数在没有执行之前，只是将函数名放入内存 import home #print dir(home) #print hasattr(home,'dev')#通过函数hasattr到内存中找到home模块，判断home模块下是否存在dev函数， #有返回True,否则返回false #print dir(home) #print getattr(home,'dev')#到内存中的home模块中去获取函数dev(其实时获取dev函数在内存中的地址) #print setattr(home,'alex','gentle man')#通过setattr对内存中的home模块添加一个字符串alex #print dir(home) #delattr(home,'dev')#通过delattr删除内存中home模块中的dev函数 #print dir(home) # """ class Foo: static_name='nba' def __init__(self): self.name='alex' def show(self): pass @staticmethod def static_show(self): pass @classmethod def class_show(cls): pass #obj=Foo() #print Foo.__dict__.keys() #查看类里面的成员 #print hasattr(Foo,'static_show') #print obj.__dict__#查看对象里有哪些成员 #print hasattr(obj,'name') #print hasattr(obj,'show')#普通方法是存储在类里， #但是这里用hasattr函数在对象obj中查找是否存在show方法， #返回了Ture，原因是在对象obj中没有找到之后会通过对象指针到创建对象的类中进一步查找， #所以这里返回True """ """ print hasattr(Foo,'__init__') print "##########分隔符①################" print hasattr(Foo,'static_name') print "##########分隔符②################" print hasattr(Foo,'show') print "##########分隔符③################" print hasattr(Foo,'static_show') print "##########分隔符④################" print hasattr(Foo,'class_show') obj=Foo() print obj.__dict__ print hasattr(obj,'show') print hasattr(obj,'__init__') print "##########分隔符①################" print hasattr(obj,'static_name') print "##########分隔符②################" print hasattr(obj,'show') print "##########分隔符③################" print hasattr(obj,'static_show') print "##########分隔符④################" print hasattr(obj,'class_show') """ """ import home cls = getattr(home,"Foo") print cls s_name = getattr(cls,'static_name') print s_name c_show = getattr(cls,'show') print c_show s_show=getattr(cls,'static_show') print s_show cla_show = getattr(cls,'class_show') print cla_show """ import home cls = getattr(cls,'Foo') obj=cls()#实例化一个对象obj name = getattr(obj,'name') print name
home.py
#!/usr/bin/env python # -*- coding:utf-8 -*- __author__ = 'ryan' def index(): return 'result home.index' def dev(): return 'result home.dev' def user(): return 'result home.user' def passwd(): return 'result home.passwd' """ class Foo: static_name='nba' def __init__(self): self.name='alex' def show(self): pass @staticmethod def static_show(self): pass @classmethod def class_show(cls): pass """
反射
fanshe.py
#!/usr/bin/env python # -*- coding:utf-8 -*- __author__ = 'ryan' url = raw_input('url:') controller,action =url.split('/') import home #action动作是一个字符串，去某个容器（模块）中去找函数，字符串即为函数名， #如果有则获取函数 func =getattr(home,action) func = dev dev1(): return 'result home.dev' ret = func() #func=getattr(home,'index') ret=func() print ret
webdemo.py
#!/usr/bin/env python #coding:utf-8 from wsgiref.simple_server import make_server def RunServer(environ, start_response): start_response('200 OK', [('Content-Type', 'text/html')]) url = environ['PATH_INFO'] temp = url.split('/')[1] import home #去home模块中检查，是否含有指定的函数 is_exist = hasattr(home, temp) #如果存在指定的函数 if is_exist: #获取函数 func = getattr(home, temp) #执行函数并获取返回值 ret = func() #将函数返回值响应响应给请求者，即浏览器 return ret else: #如果不存在函数则返回给浏览器'404 not found' return '404 not found' if __name__ == '__main__': httpd = make_server('', 8001, RunServer) print "Serving HTTP on port 8001..." httpd.serve_forever()
