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Python 反射是什么？

学习了几天，做个总结留给自己看。

感觉跟 SQL 入门要掌握的原理一样，Python 反射看起来也会做4件事，“增删查获”

增 - 增加属性，方法 

setattr

删 - 删除属性，方法

delattr

查 - 查找是否存在属性，方法

hasattr

获 - 获取属性，方法

getattr

举个例子

class Student:city = "Shanghai"def __init__(self, name, age, sex):self.name = nameself.age = ageself.sex = sexdef hello_student(self):name = self.nameprint("你好: {}".format(name))Jack = Student("Jack", 6, "123456789")print(getattr(Student, 'city'))
print(hasattr(Student, "city"))
print(hasattr(Student, "hello_student"))
print(hasattr(Student, "hello_jack"))getattr(Student, "my_info")()setattr(Jack, "name", "Tom")
print(getattr(Jack, "name"))def hello_student_new(self):name = self.nameprint("新朋好友你好: {}".format(name))setattr(Jack, "my_name", hello_student_new)
getattr(Jack, "hello_student_new")()delattr(Student, "city")
print(getattr(Student, 'city'))delattr(Student, "name")
print(getattr(Student, "name"))delattr(Student, "hello_student_new")
print(getattr(Student, "hello_student_new"))

这些例子基本涵盖了四种用法。