#!/usr/bin/env python

# -*- coding: UTF-8 -*-

# Author:Du Fei

import os

#学号，姓名，年龄，性别，身高

allStudentsList=[]

#从文件中读取数据

def readFromFile(fileName):

if not os.path.exists(fileName):# 如果文件不存在，则新增一个空文件

f = open(fileName,"w")

f.close()

with open(fileName,"r",encoding="utf-8") as f:

for onStr in f:

oneList=onStr.strip("\n").split(",")

oneList[0]=int(oneList[0])#学号

oneList[1]=oneList[1]#姓名

oneList[2]=int(oneList[2])#年龄

oneList[3]=oneList[3]#性别

oneList[4]=float(oneList[4])#身高

allStudentsList.append(oneList)

#将数据写入文件

def writeToFile(fileName):

f =open(fileName,"w")

f.close()

with open(fileName,"a",encoding="utf-8") as f:

for oneList in allStudentsList:

oneStr=str(str(oneList[0])+","+oneList[1]+","+str(oneList[2])+","+oneList[3]+","+str(oneList[4])+"\n")

f.write(oneStr)

#显示所有学生信息

def allStudentsShow():

for one in allStudentsList:

print("学号：%d,姓名：%s,年龄：%d,性别：%s,身高：%f" % (one[0], one[1], one[2], one[3],one[4]))

#新增学生

def addNewStudent(newStuList):

#check学号是否重复复

for one in allStudentsList:

if one[0] == newStuList[0]:

return -1 #学号重复

allStudentsList.append(newStuList)

writeToFile("student.txt")

return 1

#修改学生年龄

def updateStudentsAge(id,newAge):

for one in allStudentsList:

if one[0]==id:

one[2]=newAge

break

else:

return -1#找不到此学号

writeToFile("student.txt")

return 1

#删除学生

def deleteStudent(id):

index =0

for one in allStudentsList:

if one[0] ==id:

del allStudentsList[index]

break

index +=1

else:

return -1#找不到要删除的学号

writeToFile("student.txt")

return 1

#按照姓名查找

def searchStudents(name):

flag =0

for one in allStudentsList:

if one[1]==name:

print("学号：%d,姓名：%s,年龄：%d,性别：%s,身高：%f" % (one[0], one[1], one[2], one[3], one[4]))

flag=1

if flag==0:

return -1#查无此人

return 1

def sortMe(oneList):

return oneList[0]

#按序号排序

def orderById(flag):#flag:1升序，2降序

if flag==1:#升序

allStudentsList.sort(reverse=False,key=lambda oneList:oneList[0])

else:

allStudentsList.sort(reverse=True,key=sortMe)

#功能菜单

def menuShow():

print("**********************************")

print("*1.查看所有学生信息****************")

print("*2.新增学生************************")

print("*3.修改学生************************")

print("*4.删除学生************************")

print("*5.按姓名查找**********************")

print("*6.按学号排序**********************")

print("*7.保存***************************")

print("*8.退出***************************")

print("**********************************")

if __name__ == "__main__":

#从文件中读取数据

readFromFile("student.txt")

# print(allStudentsList)

while True:

# 显示主菜单

menuShow()

select =int(input("请选择功能选项："))

if select == 1:

allStudentsShow()

elif select == 2:

while True:

try:

id = int(input("请输入学号："))

name = input("请输入姓名：")

age = int(input("请输入年龄："))

sex = input("请输入性别：")

height = float(input("请输入身高："))

newStuList=[id,name,age,sex,height]

if addNewStudent(newStuList) ==-1:

print("学号已存在,请重新输入")

else:

flag=input("新增用户成功,是否继续新增(y/n)?:")

if flag.lower() !="y":

break

except:

print("输入有误请重新输入")

elif select == 3:

while True:

id=int(input("请输入序号："))

newAge=int(input("请输入新的年龄："))

if updateStudentsAge(id,newAge) ==-1:

print("找不到此学号的学生，请重新输入")

else:

flag = input("修改成功,是否继续修改(y/n)?:")

if flag.lower() != "y":

break

elif select == 4:

while True:

id =int(input("请输入删除的学号："))

if deleteStudent(id) == -1:

print("找不到此学号的学生，请重新输入")

else:

flag = input("删除成功,是否继续删除(y/n)?:")

if flag.lower() != "y":

break

elif select == 5:

while True:

name=input("请输入查找的姓名：")

if searchStudents(name) ==-1:

print("查无此人")

flag = input("是否继续查找(y/n)?:")

if flag.lower() != "y":

break

elif select == 6:

flag=int(input("请选择排序方式(1：升序，2：降序)"))

orderById(flag)

allStudentsShow()

elif select == 7:

writeToFile("student.txt")

else:

exit()

原文：https://www.cnblogs.com/coding2018/p/10072386.html