day12 python作业:员工信息表

作业要求:

周末大作业：实现员工信息表
文件存储格式如下：
id，name，age，phone，job
1,Alex,22,13651054608,IT
2,Egon,23,13304320533,Tearcher
3,nezha,25,1333235322,IT

现在需要对这个员工信息文件进行增删改查。不允许一次性将文件中的行都读入内存。

基础必做：

a.可以进行查询，支持三种语法：select 列名1，列名2，… where 列名条件,  支持：大于小于等于，还要支持模糊查找。

示例：
select name, age where age>22
select * where job=IT
select * where phone like 133

进阶选做：
b.可创建新员工记录，id要顺序增加
c.可删除指定员工记录，直接输入员工id即可
d.修改员工信息
语法：set 列名=“新的值” where 条件
#先用where查找对应人的信息，再使用set来修改列名对应的值为“新的值”

注意：要想操作员工信息表，必须先登录，登陆认证需要用装饰器完成.其他需求尽量用函数实现

作业代码:

自己鼓捣大半天,把查询功能实现了,代码没有进行优化,回头再优化代码完成进阶要求.

FLAG = False
def wrapper(func):
    def inner(*args,**kwargs):
        global FLAG
        '''登录程序'''
        if FLAG:
            ret = func(*args,**kwargs)
            return ret
        else:
            username = input('username:')
            password = input('password:')
            if username == 'pengzhaoyang' and password == '':
                FLAG = True
                ret = func(*args,**kwargs)
                return ret
            else:
                print('登录失败')
    return inner
 
@wrapper
def dayu():
    keys = vkey[0].split(',')
    sele = vkey[1].split(">")
    with open('message','r',encoding='utf-8') as f:
        for line in f:
            lis = line.strip().split(',')
            dic = {}
            s = ''
            for i in range(len(lis)):
                dic[doc[i]] = lis[i]
            if int(dic[sele[0]]) > int(sele[1]):
                if keys[0] != '*':
                    for key in keys:
                        s += dic[key] + ','
                else:
                    s = line.strip()
                print(s)
 
@wrapper
def xiaoyu():
    keys = vkey[0].split(',')
    sele = vkey[1].split("<")
    with open('message','r',encoding='utf-8') as f:
        for line in f:
            lis = line.strip().split(',')
            dic = {}
            s = ''
            for i in range(len(lis)):
                dic[doc[i]] = lis[i]
            if int(dic[sele[0]]) < int(sele[1]):
                if keys[0] != '*':
                    for key in keys:
                        s += dic[key] + ','
                else:
                    s = line.strip()
                print(s)
 
@wrapper
def dengyu():
    keys = vkey[0].split(',')
    sele = vkey[1].split("=")
    with open('message','r',encoding='utf-8') as f:
        for line in f:
            lis = line.strip().split(',')
            dic = {}
            s = ''
            for i in range(len(lis)):
                dic[doc[i]] = lis[i]
            if dic[sele[0]] == sele[1]:
                if keys[0] != '*':
                    for key in keys:
                        s += dic[key] + ','
                else:
                    s = line.strip()
                print(s)
 
@wrapper
def like():
    keys = vkey[0].split(',')
    with open('message','r',encoding='utf-8') as f:
        for line in f:
            lis = line.strip().split(',')
            dic = {}
            s = ''
            for i in range(len(lis)):
                dic[doc[i]] = lis[i]
            if vkey[-1] in dic[vkey[1]]:
                if keys[0] != '*':
                    for key in keys:
                        s += dic[key] + ','
                else:
                    s = line.strip()
                print(s)
 
doc = ['id', 'name', 'age', 'phone', 'job']
 
while True:
    sel = input('>>>')  # 输入查询命令
    if 'select' in sel and 'where' in sel:
        vkey = sel.split()[1::2]
        if '>' in sel:
            dayu()
        elif '<' in sel:
            xiaoyu()
        elif '=' in sel:
            dengyu()
        else:
            like()
    else:
        print('语法错误!!!')