反射
getattr
通过字符串从指定对象获取的属性; getattr（x，'y'）相当于x.y.
# getattr(o,name) #通过字符串从指定对象获取的属性; getattr（x，'y'）相当于x.y.
# def getattr(object, name, default=None): # known special case of getattr
"""
getattr(object, name[, default]) -> value
Get a named attribute from an object; getattr(x, 'y') is equivalent to x.y.
When a default argument is given, it is returned when the attribute doesn't
exist; without it, an exception is raised in that case.
"""
hasattr
返回对象是否具有给定名称的属性。这是通过调用getattr（obj，name）和捕获AttributeError来完成的。
# hasattr 返回对象是否具有给定名称的属性。这是通过调用getattr（obj，name）和捕获AttributeError来完成的。
# def hasattr(*args, **kwargs): # real signature unknown
# """
# Return whether the object has an attribute with the given name.
#
# This is done by calling getattr(obj, name) and catching AttributeError.
# """
# pass
setattr
将指定对象的命名属性设置为指定值。 setattr（x，'y'，v）相当于``x.y = v'' (动态添加)
# setattr 将指定对象的命名属性设置为指定值。 setattr（x，'y'，v）相当于``x.y = v'' (动态添加)
# def setattr(x, y, v): # real signature unknown; restored from __doc__
# """
# Sets the named attribute on the given object to the specified value.
#
# setattr(x, 'y', v) is equivalent to ``x.y = v''
# """
# pass
delattr 从给定对象中删除命名属性。delattr（x，'y'）相当于``del x.y' （动态删除）
# delattr 从给定对象中删除命名属性。delattr（x，'y'）相当于``del x.y' （动态删除）
# def delattr(x, y): # real signature unknown; restored from __doc__
# """
# Deletes the named attribute from the given object.
#
# delattr(x, 'y') is equivalent to ``del x.y''
# """
# pass
from prettytable import PrettyTable
class Course(object):
def __init__(self, name, price, period):
self.name = name
self.price = price
self.period = period
class Student(object):
def __init__(self, name):
self.name = name
self.all_courses = None
self.courses = []
def select_course(self):
course_id = input('请输入课程id:')
if course_id.isdigit() and 0 < int(course_id) <= len(self.all_courses):
course_id = int(course_id)
choice_course = self.all_courses[course_id - 1]
if choice_course not in self.courses:
self.courses.append(choice_course)
print('你选择的{} {}期课程已添加成功'.format(choice_course.name, choice_course.period))
else:
print('课程已存在，添加失败')
else:
print('输入有误，请重新输入！')
def show_selected_course(self):
course_table = PrettyTable(['ID', 'course_name', 'price', 'period'])
for index, item in enumerate(self.courses, 1):
c = [getattr(item, i) for i in item.__dict__]
c.insert(0, index)
course_table.add_row(c)
print(course_table)
def delete_course(self):
print('请输入ID进行删除：')
self.show_selected_course()
choice = input('>>>')
if choice.isdigit() and 0 < int(choice) <= len(self.courses):
choice = int(choice)
ret = self.courses.pop(choice - 1)
print('你选择的{} {}期课程已删除成功！'.format(ret.name, ret.period))
else:
print('你的输入有误！')
def show_all_course(self):
info = PrettyTable(['id', 'course_name', 'price', 'period'])
for index, item in enumerate(self.all_courses, 1):
lst = [getattr(item, i) for i in item.__dict__]
lst.insert(0, index)
info.add_row(lst)
print(info)
course_info = [('python', 10, 1), ('java', 20, 10),
('php', 30, 11), ('ruby', 10, 10),
('go', 10, 30), ('C', 30, 11), ('h5', 30, 10),
('C++', 10, 14), ('perl', 20, 10), ('C#', 30, 2)]
def run():
"""
1.创建10个课程
2.用户输入学生姓名，动态创建学生对象
3.查看所有课程
4.为学生选课
5.查看学生已选课程
6.删除已选课程
"""
# 创建10课程
features_list = ['select_course', 'show_selected_course', 'delete_course', 'show_all_course']
all_course = [Course(*item) for item in course_info]
student_name = input('请输入姓名:')
student = Student(student_name)
student.all_courses = all_course
print('以下是所有课程信息,请按编号选择')
student.show_all_course()
while True:
print('''1.选课
2.查看已选课程
3.删除已选课程
4.查看所有课程''')
choice = input('请输入ID进行操作[q]:')
if choice.upper() == 'Q':
return
if choice.isdigit() and 0 < int(choice) <= len(features_list):
choice = int(choice)
func = getattr(student, features_list[choice - 1])
func()
else:
print('你的选择有误！')
run()
