python3学习之路14实操练习项目学生信息管理系统

主界面：

def main():
    while True:
        menm()
        choice = int(input('请选择:'))
        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？y/n')
                if answer == 'y' or answer == 'Y':
                    print('谢谢您得使用')
                    break  #退出系统
                else:
                    continue
            elif choice == 1:
                insert()  #录入学生信息
            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 menm():
    print("==========================学生信息管理系统==========================")
    print("------------------------------功能菜单----------------------------")
    print('\t\t\t\t\t1.录入学生信息')
    print('\t\t\t\t\t2.查找学生信息')
    print('\t\t\t\t\t3.删除学生信息')
    print('\t\t\t\t\t4.修改学生信息')
    print('\t\t\t\t\t5.排序')
    print('\t\t\t\t\t6.统计学生总人数')
    print('\t\t\t\t\t7.显示所有学生信息')
    print('\t\t\t\t\t0.退出')
    print("=================================================================")

def insert():
    pass
def search():
    pass
def delete():
    pass
def modify():
    pass
def sort():
    pass
def total():
    pass
def show():
    pass

if __name__ == '__main__':
    main()
    

def insert():
    student_list = []
    while True:
        id = input('请输入ID(如1001):')
        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')
            continue
        #将录入得学生信息保存到字典
        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':
            continue
        else:
            break

    #调用save()函数
    save(student_list)
    print('学生信息录入完成！！！')

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 delete():
    while True:
        student_id = input('请输入要删除得学生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  #表示是否删除
            if student_old:
                with open(filename,'w',encoding='utf-8') as wfile:
                    d = {}
                    for item in student_old:
                        d = dict(eval(item)) #将字符串转为字典
                        if d['id'] != student_id:
                            wfile.write(str(d)+'\n')
                        else:
                            flag = True
                    if flag:
                        print(f'id为{student_id}得学生信息已经被删除')
                    else:
                        print(f'没有找到ID为{student_id}得学生信息')
            else:
                print('无学生信息')
                break
            show()  #删除之后重新显示所有学生信息
            answer = input('是否继续删除？y/n')
            if 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('请输入要修改的学生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')
        if answer == 'y':
            modify()

def search():
    student_query = []
    while True:
        id = ''
        name = ''
        if os.path.exists(filename):
            mode = input('按ID查找请输入1,按照姓名查找请输入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('是否继续查询？y/n')
            if answer == 'y':
                continue
            else:
                break
        else:
            print("暂未保存学生信息")
            return
def show_student(lst):
    if len(lst) == 0:
        print('未查询到学生信息，无数据显示！')
        return
    #定义标题的显示格式
    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 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('暂未保存学生数据信息...')

def show():
    student_lst= []
    if os.path.exists(filename):
        with open(filename,'r',encoding='utf-8') as rfile:
            students = rfile.readlines()
            for item in students:
                student_lst.append(eval(item))
            if student_lst:
                show_student(student_lst)

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('请选择排序方式（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('您的输入有误，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成绩排序 3.按java成绩排序 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('您的输入有无，请重新输入！！！')
        sort()
    show_student(student_new)

所有代码如下：

import os.path

filename= 'student.txt'

def main():
    while True:
        menm()
        choice = int(input('请选择:'))
        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？y/n')
                if answer == 'y' or answer == 'Y':
                    print('谢谢您得使用')
                    break  #退出系统
                else:
                    continue
            elif choice == 1:
                insert()  #录入学生信息
            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 menm():
    print("==========================学生信息管理系统==========================")
    print("------------------------------功能菜单----------------------------")
    print('\t\t\t\t\t1.录入学生信息')
    print('\t\t\t\t\t2.查找学生信息')
    print('\t\t\t\t\t3.删除学生信息')
    print('\t\t\t\t\t4.修改学生信息')
    print('\t\t\t\t\t5.排序')
    print('\t\t\t\t\t6.统计学生总人数')
    print('\t\t\t\t\t7.显示所有学生信息')
    print('\t\t\t\t\t0.退出')
    print("=================================================================")

def insert():
    student_list = []
    while True:
        id = input('请输入ID(如1001):')
        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')
            continue
        #将录入得学生信息保存到字典
        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':
            continue
        else:
            break

    #调用save()函数
    save(student_list)
    print('学生信息录入完成！！！')

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,按照姓名查找请输入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('是否继续查询？y/n')
            if answer == 'y':
                continue
            else:
                break
        else:
            print("暂未保存学生信息")
            return
def show_student(lst):
    if len(lst) == 0:
        print('未查询到学生信息，无数据显示！')
        return
    #定义标题的显示格式
    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('请输入要删除得学生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  #表示是否删除
            if student_old:
                with open(filename,'w',encoding='utf-8') as wfile:
                    d = {}
                    for item in student_old:
                        d = dict(eval(item)) #将字符串转为字典
                        if d['id'] != student_id:
                            wfile.write(str(d)+'\n')
                        else:
                            flag = True
                    if flag:
                        print(f'id为{student_id}得学生信息已经被删除')
                    else:
                        print(f'没有找到ID为{student_id}得学生信息')
            else:
                print('无学生信息')
                break
            show()  #删除之后重新显示所有学生信息
            answer = input('是否继续删除？y/n')
            if 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('请输入要修改的学生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')
        if 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('请选择排序方式（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('您的输入有误，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成绩排序 3.按java成绩排序 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('您的输入有无，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('暂未保存学生数据信息...')
def show():
    student_lst= []
    if os.path.exists(filename):
        with open(filename,'r',encoding='utf-8') as rfile:
            students = rfile.readlines()
            for item in students:
                student_lst.append(eval(item))
            if student_lst:
                show_student(student_lst)

if __name__ == '__main__':
    main()