python写的简答学生管理系统Demo（练习python语法）

python写的简单的学生管理系统，练习python语法。

可以运行在windows和linux下，python 2.7。

#!/usr/local/bin/python# -*- coding:utf-8 -*-import osimport re#定义学生类class Student:    def __init__(self):        self.name = ''        self.ID = ''        self.score = 0#根据学生分数进行从大到小的冒泡排序def BuddleSortByScore( stulist ):    n = len( stulist )    for i in range( n ):        for j in range( n - i - 1):            if stulist[j].score < stulist[j+1].score:                #tmp = stulist[j+1]                #stulist[j+1] = stulist[j]                #stulist[j] = tmp                stulist[j],stulist[j+1] = stulist[j+1],stulist[j]#按顺序输出所有学生的信息def PrintAllStudentInfo( stulist ):    print u"______________________学生列表_______________"    for i in range( len(stulist) ):        print u"姓名:" ,        print stulist[i].name,        print "    " ,        print u"学号:" ,        print stulist[i].ID ,        print "   " ,        print u"分数：" ,        print stulist[i].score    print "____________________________________________"#增加一个学生,增加成功返回True，否则返回Falsedef Add( stulist , stu ):    if searchByID( stulist , stu.ID ) == 1:        print u"此ID已经存在！"        return False    stulist.append( stu )    #给出是否保存更新数据的选择    print "Do you want to save the result ?"    nChoose = raw_input("Choose:Y/N:")        if nChoose == 'Y' or nChoose == 'y':        #将改变后的结果写入文件中,追加写文件        file_object = open("students.txt","a")        file_object.write( stu.ID )        file_object.write( " " )        file_object.write( stu.name )        file_object.write( " " )        file_object.write( str(stu.score) )        file_object.write( "\r\n" )        file_object.close()        return True    else:        stulist.remove(stu)#根据ID删除一个学生的信息，删除成功则返回True，否则返回falsedef DeleteByID( stulist , ID ):    for stu in stulist:        if stu.ID == ID:            stulist.remove( stu )            #选择是否保存已经改变的内容            print "Do you want to save the changed result ?"            nChoose = raw_input("Choose:Y/N:")                        if nChoose == 'Y' or nChoose == 'y':                file_object = open("students.txt" , "w+")                for stu2 in stulist:                    file_object.write(stu2.ID)                    file_object.write(" ")                    file_object.write(stu2.name)                    file_object.write(" ")                    file_object.write(str(stu2.score))                    file_object.write("\r\n")                file_object.close()                print u"删除成功!"            return True    print u"删除失败!"    return False#根据姓名删除一个学生的信息，删除成功返回True,否则返回Falsedef DeleteByName( stulist , name ):    pos = searchByName( stulist , name )    if pos != -1:        del stulist[pos]        #选择是否保存已经改变的内容        print "Do you want to save the changed result ?"        nChoose = raw_input("Choose:Y/N:")                    if nChoose == 'Y' or nChoose == 'y':             file_object = open("students.txt" , "w+")             for stu2 in stulist:                 file_object.write(stu2.ID)                 file_object.write(" ")                 file_object.write(stu2.name)                 file_object.write(" ")                 file_object.write(str(stu2.score))                 file_object.write("\r\n")             file_object.close()             print u"删除成功!"        return True    else:        print u"删除失败!"        print pos        return False#根据学号查找一个学生是否存在,存在返回学生在列表中的下标，否则返回-1def searchByID( stulist , ID ):    for i in range( len(stulist) ):        if stulist[i].ID == ID:            print u"姓名：" ,            print stulist[i].name ,            print "  " ,            print u"学号:" ,            print stulist[i].ID ,            print "   " ,            print u"分数:" ,            print stulist[i].score             return i    return -1#根据姓名查找一个学生是否存在，存在返回学生在列表中的下标,否则返回-1def searchByName( stulist , name ):    for i in range( len(stulist) ):        if stulist[i].name == name:            print u"姓名：" ,            print stulist[i].name ,            print "  " ,            print u"学号:" ,            print stulist[i].ID ,            print "   " ,            print u"分数:" ,            print stulist[i].score             return i    return -1#初始化，读取文件，更新学生信息def Init( stulist ):    print u"初始化......"        file_object = open("students.txt","r")    #按行读取文件中学生的信息    for line in file_object:        stu = Student()        line = line.strip("\n")        s = line.split(" ")        stu.ID = s[0]        stu.name = s[1]        stu.score = s[2]        stulist.append(stu)    print u"初始化成功!"                       #查找菜单def QueryMenu( stulist ):    while True:        print "******************************"        print u"根据学生的学号进行查找-------1"        print u"根据学生的姓名进行查找-------2"        print u"离开查找模块----------------3"        print "******************************"        nChoose = raw_input("请输入你的选择")        if nChoose == "1":            ID = raw_input("请输入你要输入查找的ID:")            searchByID( stulist , ID )        elif nChoose == "2":            name = raw_input("请输入你要查找的姓名:")            searchByName( stulist , name )        elif nChoose == "3":            return        else:            print u"选择输入错误，请重新输入!"            #删除模块def DeleteMenu( stulist ):    while True:        print "*****************************"        print u"根据学生的学号进行删除------1"        print u"根据学生的姓名进行删除------2"        print u"离开删除模块---------------3"        print "******************************"        nChoose = raw_input("请进行选择:")        if nChoose == "1":            ID = raw_input("请输入你要删除的ID:")            DeleteByID( stulist , ID )        elif nChoose == "2":            name = raw_input("请输入你要删除的姓名:")            DeleteByName( stulist , name )        elif nChoose == "3":            return        else:            print u"您的选择有误，请重新输入！"                                    #菜单def menu( stulist ):    while True:        print "***********************"        print u"--------菜单------------"        print u"增加学生信息---------1"        print u"查找一个学生的信息----2"        print u"删除一个学生的信息----3"        print u"输出所有学生的信息----4"        print u"根据分数排序---------5"        print u"退出程序-------------6"        print "------------------------"        print "************************"        nChoose = raw_input("请输入你的选择:")                if nChoose == "1":            stu = Student()            stu.name = raw_input("请输入学生的姓名：")            #匹配学生ID是否满足0--9中的数字            while True:                stu.ID = raw_input("请输入学生的ID:")                #创建编译一个正则表达式的模板                p = re.compile( '^[0-9]{3}$' )                if p.match( stu.ID ):                    break                else:                    print "学生的ID输入错误，正确形式应该为0--9之间的三位数字!"            #匹配学生的分数是否满足0--100之间            while True:                    stu.score = eval( raw_input("请输入学生的分数：") )                #利用普通的符号来判断分数是否符合标准                #if stu.score >= 0 and stu.score <= 100:                #   break                #利用正则表达式来判断分数是否符合标准                if re.match( "^[0-9]" ,str(stu.score) ) and stu.score<=100 and stu.score >= 0 :                    break                 else:                    print u"分数不满足实际情况，应该为0--100之间的数字!"            if Add( stulist , stu ) == 1:                print u"学生信息增加成功!"            else:                print u"学生信息增加失败!"        elif nChoose == "2":            QueryMenu( stulist )        elif nChoose == "3":            DeleteMenu( stulist )        elif nChoose == "4":            PrintAllStudentInfo( stulist )        elif nChoose == "5":            BuddleSortByScore( stulist )            print "Do you want to save the sorted result?"            choose = raw_input("please input your choice:Y/N:")            if choose == 'Y' or choose == 'y':               file_object = open("students.txt","w+")               for stu2 in stulist:                   file_object.write(stu2.ID)                   file_object.write(" ")                   file_object.write(stu2.name)                   file_object.write(" ")                   file_object.write(str(stu2.score))                   file_object.write("\r\n")        elif nChoose == "6":            return        else:            print u"输入有误，请重新输入！"             #测试函数部分if __name__ == '__main__':    #定义一个列表用来存储所有学生的信息    stulist = []        #初始化，从文件中读取信息    Init( stulist )        #菜单函数    menu( stulist )                                

运行需要读写文件Students.txt。文件格式如下图：