Python搭的学生信息管理系统

import os.path
filename='student.txt'
def main():
    while True:
        menu()
        choice=int(input('请输入您要用的功能'))
        if choice in [0,1,2,3,4,5,6,7]:
            if choice==0:
                answer=input('您确定要退出系统吗？')
                if answer=='y' or answer=='Y':
                    print('谢谢您的使用')
                    break
                else:
                    continue
            elif choice==1:
                insert()
            elif choice==2:
                search()
            elif choice==3:
                delete()
            elif choice==4:
                modify()
            elif choice==5:
                sort()
            elif choice==6:
                total()
            elif choice==7:
                show()
 
def menu():
    print('------------------------学生信息管理系统----------------------------------')
    print('-------------------------功能菜单---------------------------------------')
    print('\t\t\t\t1.录入学生信息')
    print('\t\t\t\t2.查找学生信息')
    print('\t\t\t\t3.删除学生信息')
    print('\t\t\t\t4.修改学生信息')
    print('\t\t\t\t5.排序')
    print('\t\t\t\t6.统计学生总人数')
    print('\t\t\t\t7.显示所有学生信息')
    print('\t\t\t\t0.退出系统')
    print('-------------------------------------------------------------------------')
 
def insert():
    student_list=[]
    while True:
        id=input('请输入id:')
        if not id:
            break
        name=input('请输入姓名:')
        if not name:
            break
        try:
            english=int(input('请输入英语成绩:'))
            python=int(input('请输入python成绩:'))
            java=int(input('请输入java成绩:'))
        except:
            print('输入无效，不是整数类型，请重新输入')
 
        #将录入的学生信息保存到字典中
        student={'id':id,'name':name,'english':english,'python':python,'java':java}
        #将学生信息添加到列表中
        student_list.append(student)
        answer=input('是否继续添加?y/n\n')
        if answer=='y' or answer=='Y':
            continue
        else:
            break
    save(student_list)
    print('学生信息录入完毕')
 
def save(lst):
    try:
        stu_txt=open(filename,'a',encoding='utf-8')
    except:
        stu_txt=open(filename,'w',encoding='utf-8')
    for item in lst:
        stu_txt.write(str(item)+'\n')
    stu_txt.close()
 
def search():
    student_query=[]
    while True:
        id=''
        name=''
        if os.path.exists(filename):
            mode=input('按ID查找请输入1，按姓名查找请输入2:')
            if mode=='1':
                id=input('请输入学生ID')
            elif mode=='2':
                name=input('请输入学生姓名:')
            else:
                print('您的输入有误，请重新输入')
                search()
            with open(filename,'r',encoding='utf-8') as rfile:
                student=rfile.readlines()
                for item in student:
                    d=dict(eval(item))
                    if id!='':
                        if d['id']==id:
                            student_query.append(d)
                        elif name!='':
                            if d['name']==name:
                                student_query.append(d)
            #显示查询结果
            show_student(student_query)
            #清空列表
            student_query.clear()
            answer=input('是否要继续查询?y/n\n')
            if answer=='y' or answer=='Y':
                continue
            else:
                break
        else:
            print('暂未保存学生信息')
            return
 
def show_student(lst):
    if len(lst)=='':
        print('没有查询到学生信息，无数据显示！！！')
        return
    #定义标题显示格式
    format_title='{:^6}\t{:^12}\t{:^8}\t{:^10}\t{:^10}\t{:^8}'
    print(format_title.format('ID','姓名','英语成绩','Python成绩','Java成绩','总成绩'))
    #定义内容的显示格式
    format_data='{:^6}\t{:^12}\t{:^8}\t{:^8}\t{:^8}\t{:^8}'
    for item in lst:
        print(format_data.format(item.get('id'),
                                 item.get('name'),
                                 item.get('english'),
                                 item.get('python'),
                                 item.get('java'),
                                 int(item.get('english'))+int(item.get('python'))+int(item.get('java'))
 
        ))
 
def delete():
    while True:
        student_id=input('请输入要删除的学生的ID:')
        if student_id!='':
            if os.path.exists(filename):
                with open(filename,'r',encoding='utf-8') as file:
                    student_old=file.readlines()
            else:
                student_old=[]
            flag=False  #标记是否删除
            if student_old:
                with open(filename,'w',encoding='utf-8') as wfile:
                    d={}
                    for item in student_old:
                        d=dict(eval(item))  #将字符串转成字典
                        if d['id']!=student_id:
                            wfile.write(str(d)+'\n')
                        else:
                            flag=True
                    if flag:
                        print(f'id未{student_id}的学生信息已被删除')
                    else:
                        print(f'没有找到ID为{student_id}的学生信息')
            else:
                print('无学生信息')
                break
            show()
            answer=input('是否继续删除?y/n\n')
            if answer=='y' or answer=='Y':
                continue
            else:
                break
 
def modify():
    show()
    if os.path.exists(filename):
        with open(filename,'r',encoding='utf-8') as rfile:
            student_old=rfile.readlines()
    else:
        return
    student_id=input('请输入要修改的学员的ID:')
    with open(filename,'w',encoding='utf-8') as wfile:
        for item in student_old:
            d=dict(eval(item))
            if d['id']==student_id:
                print('找到学生信息，可以修改他的相关信息!')
                while True:
                    try:
                        d['name']=input('请输入姓名:')
                        d['english']=input('请输入英语成绩:')
                        d['python']=input('请输入python成绩:')
                        d['java']=input('请输入java成绩:')
                    except:
                        print('您的输入有误，请重新输入!')
                    else:
                        break
                wfile.write(str(d)+'\n')
                print('修改成功！！！')
 
            else:
                wfile.write(str(d)+'\n')
        answer=input('是否继续修改其他学生信息？y/n\n')
        if answer=='y' or answer=='Y':
            modify()
 
def sort():
    show()
    if os.path.exists(filename):
        with open(filename,'r',encoding='utf-8') as rfile:
            student_list=rfile.readlines()
        student_new=[]
        for item in student_list:
            d=dict(eval(item))
            student_new.append(d)
    else:
        return
    asc_or_desc=input('请选择(0.升序 1.降序):')
    if asc_or_desc=='0':
        asc_or_desc_bool=False
    elif asc_or_desc=='1':
        asc_or_desc_bool=True
    else:
        print('您输入的有误，请重新输入')
        sort()
    mode=input('请选择排序方式(1.按英语成绩排序 2.按Python成绩牌序 3.按Java成绩牌序 0.按总成绩排序):')
    if mode=='1':
        student_new.sort(key=lambda x :int(x['english']),reverse=asc_or_desc_bool)
 
    elif mode=='2':
        student_new.sort(key=lambda x: int(x['python']),reverse=asc_or_desc_bool)
    elif mode=='3':
        student_new.sort(key=lambda x: int(x['java']),reverse=asc_or_desc_bool)
    elif mode=='0':
        student_new.sort(key=lambda x: int(x['english'])+int(x['python'])+ int(x['java']),reverse=asc_or_desc_bool)
    else:
        print('您输入的有误，请重新输入!!!')
        sort()
    show_student(student_new)
 
def total():
    if os.path.exists(filename):
        with open(filename,'r',encoding='utf-8') as rfile:
            students=rfile.readlines()
            if students:
                print(f'一共有{len(students)}名学生')
            else:
                print('还没有录入学生信息')
    else:
        print('暂未保存数据信息')
def show():
    student_list=[]
    if os.path.exists(filename):
        with open(filename,'r',encoding='utf-8') as rfile:
            students=rfile.readlines()
        for item in students:
            student_list.append(eval(item))
        if student_list:
            show_student(student_list)
    else:
        print('暂未保存数据信息！')
 
if __name__ == '__main__':
    main()