Python学习笔记14：基于mysql的学生管理系统

import pymysql
import re

def idinput(string):
    ID = input(string)
    pattern = re.compile("^\d{1,3}$")
    while not re.match(pattern, ID):
        ID = input("请输入1-3位整数:")
    return ID

def appendStudentInfo():
    ID =idinput("请输入学生学号：")
    db=pymysql.connect(host="127.0.0.1",user="root",passwd="hisense",db="test",port=3306,charset="utf8")
    cursor=db.cursor()
    sql = "select * from StuSys where ID = '%s'" % ID
    cursor.execute(sql)
    while cursor.rowcount > 0 :
        ID = idinput("该学号已存在，请重新输入:")
        sql = "select * from StuSys where ID = '%d'" % int(ID)
        cursor.execute(sql)

    name=input("请输入学生姓名：")

    chinese=input("请输入语文成绩：")
    while not chinese.isdigit() or int(chinese)>100 or int(chinese)<0:
        chinese = input("输入错误，请重新输入：")

    math =input("请输入数学成绩：")
    while not math.isdigit() or int(math) > 100 or int(math) < 0:
        math = input("输入错误，请重新输入：")

    english=input("请输入英语成绩：")
    while not english.isdigit() or int(english) > 100 or int(english) < 0:
        english = input("输入错误，请重新输入：")

    total=int(chinese)+int(math)+int(english)

    sql="""INSERT INTO StuSys(ID,
         NAME,CHINESE,ENGLISH,MATH,TOTAL)
         VALUES (%s,%s,%s,%s,%s,%s)"""
    cursor.execute(sql,(ID,name,chinese,english,math,total))
    db.commit()
    db.close()

def delstudent():
    delstudentid = idinput("请输入要删除的学生学号：")
    if  querystudent(delstudentid):
        select = input("是否删除：是(Y)/否（N）")
        if select == "Y" or select == "y":
            db = pymysql.connect(host="127.0.0.1", user="root", passwd="hisense", db="test", port=3306, charset="utf8")
            cursor = db.cursor()
            sql = "delete from stusys where ID =%s" %delstudentid
            cursor.execute(sql)
            db.commit()
            db.close()
            print("删除成功")
        elif select == "N" or select == "n":
            print("取消删除")
        else:
            print("输入错误")


def querystudent(querystudentid):
    db=pymysql.connect(host="127.0.0.1",user="root",passwd="hisense",db="test",port=3306,charset="utf8")
    cursor=db.cursor()
    sql="select * from stusys where ID=%s"%querystudentid
    cursor.execute(sql)
    if cursor.rowcount ==0 :
        print("不存在该学生信息")
        return False
    else:
        print("该学生信息如下：")
        results =cursor.fetchall()
        print("ID=%d,NAME=%s,CHINESE=%d,ENGLISH=%d,MATH=%d,TOTAL=%d" % \
          (results[0][0], results[0][1], results[0][2], results[0][3], results[0][4],results[0][5]))
        return True

def modifystudentifo():
    modifyid = idinput("请输入要的学生学号：")
    if  querystudent(modifyid):
        name = input("请重新输入学生姓名：")

        chinese = input("请重新输入语文成绩：")
        while not chinese.isdigit() or int(chinese) > 100 or int(chinese) < 0:
            chinese = input("输入错误，请重新输入：")

        math = input("请重新输入数学成绩：")
        while not math.isdigit() or int(math) > 100 or int(math) < 0:
            math = input("输入错误，请重新输入：")

        english = input("请重新输入英语成绩：")
        while not english.isdigit() or int(english) > 100 or int(english) < 0:
            english = input("输入错误，请重新输入：")

        total = int(chinese) + int(math) + int(english)
        db = pymysql.connect(host="127.0.0.1", user="root", passwd="hisense", db="test", port=3306, charset="utf8")
        cursor = db.cursor()
        sql1="update stusys set name ='%s' where id = %s"%(name,modifyid)
        cursor.execute(sql1)
        sql2="update stusys set math = %s where id = %s"%(math,modifyid)
        cursor.execute(sql2)
        sql3 = "update stusys set english = %s where id =%s"%(english,modifyid)
        cursor.execute(sql3)
        sql4 = "update stusys set total = %s where id = %s"%(total,modifyid)
        cursor.execute(sql4)
        sql5 = "update stusys set chinese = %s where id = %s"%(chinese,modifyid)
        cursor.execute(sql5)
        db.commit()
        db.close()

def allinfo():
    db=pymysql.connect(host="127.0.0.1",user="root",passwd="hisense",db="test",port=3306,charset="utf8")
    cursor=db.cursor()
    sql="select * from stusys"
    cursor.execute(sql)
    results= cursor.fetchall()
    for row in results:
        ID = row[0]
        NAME = row[1]
        CHINESE = row[2]
        ENGLISH = row[3]
        MATH = row[4]
        TOTAL = row[5]
        # 打印结果
        print("ID=%d,NAME=%s,CHINESE=%d,ENGLISH=%d,MATH=%d,TOTAL=%d" % \
              (ID, NAME, CHINESE, ENGLISH, MATH,TOTAL))

def studentMenu():
    print("="*30)
    print("学生管理系统")
    print("1、添加学生信息")
    print("2、删除学生信息")
    print("3、查询学生信息")
    print("4、修改学生信息")
    print("5、全部学生信息")
    print("6、退出")
    print("="*30)



if __name__ == '__main__':

    while True:
        studentMenu()
        menuindex = input("请输入选项序号：")
        while not menuindex.isdigit():
            menuindex = input("输入错误，请重新输入：")
        if int(menuindex) ==1:
          appendStudentInfo()
        elif int(menuindex) ==2:
           delstudent()
        elif int(menuindex) ==3:
            querystudentid = idinput("请输入要查询的学生学号：")
            querystudent(querystudentid)
        elif int(menuindex) ==4:
             modifystudentifo()
        elif int(menuindex) == 5:
             allinfo()
        elif int(menuindex) == 6:
            break
        else:
           print("输入序号无效")