作业需求：
1. 员工信息表程序，实现增删改查操作：
2. 可进行模糊查询，语法至少支持下面3种:
select name,age from staff_table where age > 22
select * from staff_table where dept = "IT"
select * from staff_table where enroll_date like "2013"
查到的信息，打印后，最后面还要显示查到的条数
3. 可创建新员工纪录，以phone做唯一键，staff_id需自增
4. 可删除指定员工信息纪录，输入员工id，即可删除
5. 可修改员工信息，语法如下:
UPDATE staff_table SET dept="Market" where dept = "IT"
6. 注意：以上需求，要充分使用函数，请尽你的最大限度来减少重复代码
思路解析：
1. 将原始员工信息记录到文件
2. 读取文件并添加到列表，进行添加删除更新操作，并写入到文件中
程序核心代码:
peopledb
1,Jack Wang,30,43304320533,INS,2015-05-03 2,Alex Li,22,23651054608,IT,2013-04-01
员工信息表.py
#!/usr/bin/env python
# -*- coding:utf-8 -*-
# Author: Colin Yao
"""python 员工信息表操作"""
import sys
import os def select1():
'''
查看文件函数
:return:
'''
with open('peopledb', 'r', encoding='utf-8') as f:
line = f.readlines()
for i in line:
print(i)
def select():
'''
查询函数
:return:
'''
msg = '''
请输入或复制查询命令例如： 1. select name,age from staff_table where age > 22
2. select * from staff_table where dept = "IT"
3. select * from staff_table where enroll_date like "2013"
'''
print(msg)
user_choice_input = input(">>>:")
user_choice_input1 = user_choice_input.split(' ')
if user_choice_input == 'select name,age from staff_table where age > %s' % (user_choice_input1[7]):
with open('peopledb', 'r+', encoding='utf-8') as f:
list1 = []
count = 0
for line in f:
i = line.strip().split(',')
if i[2] > user_choice_input1[7]:
list1.append(i)
for s in list1:
count = count + 1
for j in list1:
print(j)
print('满足条件的个数为>>:%s' % (count))
elif user_choice_input == ('select * from staff_table where dept = %s' % (user_choice_input1[7])):
with open('peopledb', 'r+', encoding='utf-8') as f:
list2 = []
count = 0
for line in f:
i1 = line.strip().split(',')
if i1[4] == eval(user_choice_input1[7]):
list2.append(i1)
for s1 in list2:
count = count + 1
# print(list1)
for j1 in list2:
print(j1)
print('满足条件的个数为>>:%s' % (count))
elif user_choice_input == ('select * from staff_table where enroll_date like %s' % (user_choice_input1[7])):
with open('peopledb', 'r+', encoding='utf-8') as f:
list3 = []
list4 = []
count = 0
for line in f:
i = line.strip().split(',')
list3.append(i)
for j in list3:
m = j[5].split('-')
if m[0] == eval(user_choice_input1[7]):
list4.append(j)
for s in list4:
count = count + 1
if count < 1:
print("没有找到类似的条目:")
pass
else:
pass
for j in list4:
print(j)
print('满足条件的条数为>>:%s' % (count))
return () def alter():
'''
添加函数
:return:
'''
msg = ''' 1)添加命令如下：Jack Wang,30,13304320533,HR,2015-05-03 '''
print(msg)
user_choice_input = input("请输入命令>>>:")
user_choice_input1 = user_choice_input.split(',')
with open('peopledb', 'r+', encoding='utf-8') as f:
list = []
for line in f:
s2 = line.strip().split(',')
m = s2[3]
list.append(m)
if user_choice_input1[2] in list:
print('这条记录已经存在')
main()
else:
my_index = str(len(list) + 1)
user_choice_input1.insert(0, my_index)
user_choice_input1 = ','.join(user_choice_input1)
f.write('\n')
f.write(user_choice_input1)
f.close()
print("记录添加完成", '\n')
select1()
return () def delect():
'''
删除函数
:return:
'''
print("请输入删除命令例如: 输入用户ID 既可以从staff_table里删除")
msg = '''
1)按1 删除、直接删除ID即可
2)按2或者q退出
3)按任意返回上一层
'''
print(msg)
user_choice_input = input("请输入命令>>>: ")
if user_choice_input == '':
print("现有的用户为:")
select1()
print('\n')
user_choice_input1 = input("请输入需要删除的用户ID:")
user_choice_input2 = user_choice_input1[0]
f = open('peopledb', 'r+', encoding='utf-8')
f1 = open('new_peopledb', 'w+', encoding='utf-8')
for line in f:
i = line.strip().split(',')
i1 = i[0]
if user_choice_input2 != i1:
i = ','.join(i)
f1.write(i)
f1.write('\n')
else:
continue
f.close()
f1.close()
os.remove('peopledb')
os.rename('new_peopledb', 'peopledb')
print('\n')
select1()
elif user_choice_input == '' or 'q':
sys.exit()
return () def update():
'''
更新函数
:return:
'''
msg = '''
1)这里第一个等号按照没有空格的格式划分
2)命令范例:UPDATE staff_table SET dept="INS" where dept = "HR"
'''
print(msg)
user_choice_input = input("请输入命令>>>:")
user_choice_input1 = user_choice_input.split(' ')
dept = user_choice_input1[3].split('=')
dept_new = dept[1]
dept_old = user_choice_input1[7]
if user_choice_input == ('UPDATE staff_table SET dept=%s where dept = %s' % (dept_new, dept_old)):
dept_new1 = eval(dept_new)
dept_old1 = eval(dept_old)
f = open('peopledb', 'r+', encoding='utf-8')
f1 = open('new_peopledb', 'w+', encoding='utf-8')
for line in f:
i = line.strip().split(',')
dept_change = i[4]
if dept_change == dept_old1:
i[4] = eval(dept_new)
i = ','.join(i)
f1.write(i)
f1.write('\n')
f.close()
f1.close()
os.remove('peopledb')
os.rename('new_peopledb', 'peopledb')
print('\n')
select1()
pass
return () def main():
'''
交互程序
:return:
'''
print("员工信息表操作作业练习")
msg = '''
1）查询
2）添加
3）删除
4）更新
5) 退出
'''
exit_flag = False
while not exit_flag:
print(msg)
user_choice = input("请选择>>:")
if user_choice == '':
select()
elif user_choice == '':
alter()
elif user_choice == '':
delect()
elif user_choice == '':
update()
elif user_choice == '' or 'q':
sys.exit()
else:
print("您的选择有误、请重新输入") main()