Python异常中的断言

断言的功能--assert

• 用于判断一个表达式，在表达到条件为false的时候触发异常

断言的用法--assert

• 用法:
  • assert expression, message
• 参数:
  • expression: 表达式，一般是判断相等，或者判断是某种数据类型的bool判断的语句
  • message: 具体的错误信息，非必填

• 返回值：无

  
  

isinstance函数

• 用于判断对比数据是否为目标数据类型
• isinstance(对比的数据，目标数据类型)
• 返回bool类型

对学生信息库进行异常调整

#!/usr/bin/python3
# -*- coding: utf-8 -*-
# @Time     : 2021/8/14 13:32
# @Author   : InsaneLoafer
# @File     : test.py

"""
   学生信息库
"""

class NotArgError(Exception):
    def __init__(self, message):
        self.message = message

class StudentsInfo(object):
    def __init__(self, students):
        self.students = students

    def get_by_id(self, student_id):
        return self.students.get(student_id)

    def get_all(self):
        for id_, value in self.students.items():
            print('学号{}，姓名{}，年龄{}，性别{}，班级{}'.format(
                id_, value['name'], value['age'], value['sex'], value['class_number']
            ))
        return self.students

    def add(self, **student):
        try:
            self.check_user_info(**student)
        except Exception as e:
            raise e
        self.__add(**student)

    # 实现批量添加
    def adds(self, new_students):
        for student in new_students:
            try:
                self.check_user_info(**student)
            except Exception as e:
                print(e)
                continue
            self.__add(**student)

    def __add(self, **student):
        new_id = max(self.students) + 1
        self.students[new_id] = student

    def delete(self, student_id):
        if student_id not in self.students:
            print('{}并不存在'.format(student_id))
        else:
            user_info = self.students.pop(student_id)
            print('学号是{}，{}同学的信息已被删除'.format(
                student_id, user_info
            ))

    def deletes(self, ids):
        for id_ in ids:
            if id_ not in self.students:
                print(f'{id_} 不存在学生库中')
                continue
            student_info = self.students.pop(id_)
            print(f'学号{id_} 学生 {student_info["name"]} 已被移除')

    def update(self, student_id, **kwargs):
        if student_id not in self.students:
            print('并不存在这个学号{}'.format(student_id))
            return
        try:
            self.check_user_info(**kwargs)
        except Exception as e:
            raise e

        self.students[student_id] = kwargs
        print('同学信息更新完毕')

    def updates(self, update_students):
        for student in update_students:
            try:
                id_ = list(student.keys())[0]
            except IndexError as e:
                print(e)
                continue
            if id_ not in self.students:
                print(f'学号{id_} 不存在')
                continue
            user_info = student[id_]
            try:
                self.check_user_info(**user_info)
            except Exception as e:
                print(e)
                continue
            self.students[id_] = user_info
        print('所有用户信息更新完成')

    def search_users(self, **kwargs):
        assert len(kwargs) == 1, '参数数量传递错误'

        values = list(self.students.values())
        key = None
        value = None
        result = []

        if 'name' in kwargs:
            key = 'name'
            value = kwargs[key]
        elif 'sex' in kwargs:
            key = 'sex'
            value = kwargs[key]
        elif 'class_number' in kwargs:
            key = 'class_number'
            value = kwargs[key]
        elif 'age' in kwargs:
            key = 'age'
            value = kwargs[key]
        else:
            raise NotArgError('没有发现搜索的关键字')

        for user in values:
            if value in user[key]:  # 实现模糊查找
                result.append(user)
        return result

    def check_user_info(self, **kwargs):
        assert len(kwargs) == 4, '参数必须是4个'
        if 'name' not in kwargs:
            raise NotArgError('没有发现学生姓名')

        if 'age' not in kwargs:
            raise NotArgError('缺少学生年龄')

        if 'sex' not in kwargs:
            raise NotArgError('缺少学生性别')

        if 'class_number' not in kwargs:
            raise NotArgError('缺少学生班级')

        name_value = kwargs['name']
        age_value = kwargs['age']
        sex_value = kwargs['sex']
        class_number_value = kwargs['class_number']

        if not isinstance(name_value, str):
            raise TypeError('name 应该是字符串类型')
        if not isinstance(age_value, int):
            raise TypeError('age 应该是整型')
        if not isinstance(sex_value, str):
            raise TypeError('sex 应该是字符串类型')
        if not isinstance(class_number_value, str):
            raise TypeError('class_number 应该是字符串类型')


students = {
    1: {
        'name': 'insane',
        'age': 23,
        'class_number': 'A',
        'sex': 'boy'
    },
    2: {
        'name': 'loafer',
        'age': 24,
        'class_number': 'B',
        'sex': 'boy'
    },
    3: {
        'name': 'Nancy',
        'age': 25,
        'class_number': 'A',
        'sex': 'girl'
    },
    4: {
        'name': 'xiaogao',
        'age': 26,
        'class_number': 'C',
        'sex': 'boy'
    },
    5: {
        'name': 'xiaoyun',
        'age': 18,
        'class_number': 'B',
        'sex': 'girl'
    }
}

if __name__ == '__main__':
    student_info = StudentsInfo(students=students)
    user = student_info.get_by_id(2)
    print(user)
    student_info.add(name='123', age=23, class_number='B', sex='boy')
    print(student_info.students)
    users = [
        {'name': 'xiaohua', 'age': 23, 'class_number': 'C', 'sex': 'boy'},
        {'name': 'xiaoming', 'age': 23, 'class_number': 'B', 'sex': 'boy'},
    ]
    student_info.adds(users)
    student_info.get_all()
    print('-----------')
    student_info.deletes([7, 8])
    student_info.get_all()
    print('-----------')
    student_info.updates([
        {1: {'name': 'insaneloafer', 'age': 18, 'class_number': 'A', 'sex': 'boy'}},
        {2: {'name': 'opadf', 'age': 18, 'class_number': 'B', 'sex': 'boy'}}
    ])
    student_info.get_all()
    print('--------')
    result = student_info.search_users(name='xiao')  # 模糊查询姓名含油xiao的学生信息
    print(result)
    print('--------')
    result = student_info.search_users(name='')
    print(result)  # 打印所有信息

{'name': 'loafer', 'age': 24, 'class_number': 'B', 'sex': 'boy'}
{1: {'name': 'insane', 'age': 23, 'class_number': 'A', 'sex': 'boy'}, 2: {'name': 'loafer', 'age': 24, 'class_number': 'B', 'sex': 'boy'}, 3: {'name': 'Nancy', 'age': 25, 'class_number': 'A', 'sex': 'girl'}, 4: {'name': 'xiaogao', 'age': 26, 'class_number': 'C', 'sex': 'boy'}, 5: {'name': 'xiaoyun', 'age': 18, 'class_number': 'B', 'sex': 'girl'}, 6: {'name': '123', 'age': 23, 'class_number': 'B', 'sex': 'boy'}}
学号1，姓名insane，年龄23，性别boy，班级A
学号2，姓名loafer，年龄24，性别boy，班级B
学号3，姓名Nancy，年龄25，性别girl，班级A
学号4，姓名xiaogao，年龄26，性别boy，班级C
学号5，姓名xiaoyun，年龄18，性别girl，班级B
学号6，姓名123，年龄23，性别boy，班级B
学号7，姓名xiaohua，年龄23，性别boy，班级C
学号8，姓名xiaoming，年龄23，性别boy，班级B
-----------
学号7 学生 xiaohua 已被移除
学号8 学生 xiaoming 已被移除
学号1，姓名insane，年龄23，性别boy，班级A
学号2，姓名loafer，年龄24，性别boy，班级B
学号3，姓名Nancy，年龄25，性别girl，班级A
学号4，姓名xiaogao，年龄26，性别boy，班级C
学号5，姓名xiaoyun，年龄18，性别girl，班级B
学号6，姓名123，年龄23，性别boy，班级B
-----------
所有用户信息更新完成
学号1，姓名insaneloafer，年龄18，性别boy，班级A
学号2，姓名opadf，年龄18，性别boy，班级B
学号3，姓名Nancy，年龄25，性别girl，班级A
学号4，姓名xiaogao，年龄26，性别boy，班级C
学号5，姓名xiaoyun，年龄18，性别girl，班级B
学号6，姓名123，年龄23，性别boy，班级B
--------
[{'name': 'xiaogao', 'age': 26, 'class_number': 'C', 'sex': 'boy'}, {'name': 'xiaoyun', 'age': 18, 'class_number': 'B', 'sex': 'girl'}]
--------
[{'name': 'insaneloafer', 'age': 18, 'class_number': 'A', 'sex': 'boy'}, {'name': 'opadf', 'age': 18, 'class_number': 'B', 'sex': 'boy'}, {'name': 'Nancy', 'age': 25, 'class_number': 'A', 'sex': 'girl'}, {'name': 'xiaogao', 'age': 26, 'class_number': 'C', 'sex': 'boy'}, {'name': 'xiaoyun', 'age': 18, 'class_number': 'B', 'sex': 'girl'}, {'name': '123', 'age': 23, 'class_number': 'B', 'sex': 'boy'}]

Process finished with exit code 0