老师要求用双端链表，感觉是我的败笔

效果：

# !/usr/bin/env python# -*- codeing: utf-8 -*-"""双链表模块，没啥用，直接用SQL操作更好"""__author__ = 'bearcarl'__version__= '1.0'"""结点类"""class Node(object):    def __init__(self, data = []):        self.data = data        self.pre = None        self.next = Noneclass DouLink(object):    """初始化双向链表"""    def __init__(self):        self.head = Node('head')        self.length = 1    def add(self, value):        p = self.head        new = Node(value)        while p.next:            p = p.next        p.next = new        new.pre = p        self.length += 1    def remove(self, ID):        p = self.head        while p.next:            if p.data[0] == ID:                temp = p.pre                ans = p.next                temp.next = ans                ans.pre = temp                return p                self.length -= 1            else:                p = p.next        raise AttributeError(u"can't find this element")    def release(self):        self.head = Node('head')        self.length = 1    def find(self, value, key):        results = []        p = self.head        while p.next:            # 检测下类型, 有时候会 int 和 str 比较看不出来            # print(type(key))            # print(type(value))            # print(type(p.data[2]))            if key == 0 and str(p.data[0]) == value:                results.append(p.data)            elif key == 1 and p.data[1] == value:                results.append(p.data)            elif key == 2 and str(p.data[2]) == value:                results.append(p.data)            p = p.next        print(len(results))        if len(results) > 0:            print(results)            return results        raise AttributeError(u"can't find this element")

# !/usr/bin/env python# -*- codeing: utf-8 -*-"""数据库连接模块    __init__：初始化连接信息    insert(self, insert_words)：添加字段方法    select(self, select_words)：查找字段方法    update(self, update_words)：更新字段方法    delete(self, delete_words)：删除字段方法"""__author__ = 'bearcarl'__version__= '1.0'import pymysqlclass Mysql_conn:    def __init__(self):        self.db = pymysql.connect("localhost", "root", "xxxxxxxxx", "test1")        self.cursor = self.db.cursor()    def insert(self, insert_words):        try:            # 执行sql语句            self.cursor.execute(insert_words)            # 提交到数据库执行            self.db.commit()        except:            # 如果发生错误则回滚            self.db.rollback()    def select(self, select_words):        try:            # 执行SQL语句            self.cursor.execute(select_words)            # 获取所有记录列表            results = self.cursor.fetchall()            return results        except:            print("Error: unable to fetch data")    def update(self, update_words):        try:            # 执行SQL语句            self.cursor.execute(update_words)            # 提交到数据库执行            self.db.commit()        except:            # 发生错误时回滚            self.db.rollback()    def delete(self, delete_words):        try:            # 执行SQL语句            self.cursor.execute(delete_words)            # 提交修改            self.db.commit()        except:            # 发生错误时回滚            self.db.rollback()    def close_conn(self):        self.db.close()# 测试代码# test1 = mysql_conn()# 查找测试# sw = "SELECT * FROM employee"# test1.select(sw)# 增添测试# iw = """INSERT INTO EMPLOYEE(FIRSTNAME,#          LASTNAME, AGE, SEX, INCOME)#          VALUES ('Mac', 'Mohan', 20, 'M', 2000)"""# test1.insert(iw)# 更新测试# uw = "UPDATE EMPLOYEE SET AGE = AGE + 1 WHERE SEX = '%s'" % ('man')# test1.update(uw)# 删除测试# dw = "DELETE FROM EMPLOYEE WHERE AGE = '%d'" % (20)# test1.delete(dw)# test1.close_conn()

# !/usr/bin/env python# -*- codeing: utf-8 -*-"""GUI 模块， 整个系统的核心，在这个模块中调用 dLink 模块和 connect_mysql模块参考资料：    https://www.cnblogs.com/shemingli/p/6354073.html    entry https://blog.csdn.net/liuxu0703/article/details/60781107    Tkinter 15种控件简介  https://blog.csdn.net/qq_25600055/article/details/46941895    Grid布局管理器详解 https://www.cnblogs.com/ruo-li-suo-yi/p/7425307.html    Listbox https://blog.csdn.net/m0_37264397/article/details/79079259            https://blog.csdn.net/aa1049372051/article/details/51878578            https://blog.csdn.net/jcodeer/article/details/1811310    messagebox  http://www.17python.com/blog/25"""__author__ = 'bearcarl'__version__= '1.0'from tkinter import *from tkinter import ttkfrom tkinter import messagebox  # 导入提示窗口包from connect_mysql import Mysql_connfrom dLink import DouLink, Node# 设置窗口大小def center_window(root, width, height):    screenwidth = root.winfo_screenwidth()    screenheight = root.winfo_screenheight()    size = '%dx%d+%d+%d' % (width, height, (screenwidth - width) / 2, (screenheight - height) / 2)    root.geometry(size)class GUI:    """给每个组件都命名是为了以后迭代方便"""    def __init__(self, root):        # 创建双向链表        self.dl = DouLink()        root.title('学员信息管理系统  http://www.bearcarl.top')        # 设置窗口大小        center_window(root, 800, 600)        root.maxsize(1200, 800)        root.minsize(300, 240)        root.iconbitmap('1.ico')        # 添加学员        upload_label_1 = ttk.Label(root, text='姓名').grid(row=0, column=1)        upload_label_2 = ttk.Label(root, text='年龄').grid(row=1, column=1)        upload_label_3 = ttk.Label(root, text='电话号码').grid(row=2, column=1)        upload_label_4 = ttk.Label(root, text='入学日期').grid(row=3, column=1)        upload_label_5 = ttk.Label(root, text='邮箱').grid(row=4, column=1)        upload_entry_1 = ttk.Entry(root)        upload_entry_2 = ttk.Entry(root)        upload_entry_3 = ttk.Entry(root)        upload_entry_4 = ttk.Entry(root)        upload_entry_5 = ttk.Entry(root)        upload_entry_1.grid(row=0, column=2)        upload_entry_2.grid(row=1, column=2)        upload_entry_3.grid(row=2, column=2)        upload_entry_4.grid(row=3, column=2)        upload_entry_5.grid(row=4, column=2)        upload_button_1 = ttk.Button(root, text="提交信息", command=lambda: upload_event()).grid(row=6, column=2)        # 修改信息        update_label_1 = ttk.Label(root, text='需更新学号').grid(row=0, column=3)        update_label_2 = ttk.Label(root, text='姓名').grid(row=1, column=3)        update_label_3 = ttk.Label(root, text='年龄').grid(row=2, column=3)        update_label_4 = ttk.Label(root, text='电话号码').grid(row=3, column=3)        update_label_5 = ttk.Label(root, text='入学日期').grid(row=4, column=3)        update_label_6 = ttk.Label(root, text='邮箱').grid(row=5, column=3)        update_entry_1 = ttk.Entry(root)        update_entry_2 = ttk.Entry(root)        update_entry_3 = ttk.Entry(root)        update_entry_4 = ttk.Entry(root)        update_entry_5 = ttk.Entry(root)        update_entry_6 = ttk.Entry(root)        update_entry_1.grid(row=0, column=4)        update_entry_2.grid(row=1, column=4)        update_entry_3.grid(row=2, column=4)        update_entry_4.grid(row=3, column=4)        update_entry_5.grid(row=4, column=4)        update_entry_6.grid(row=5, column=4)        update_button = ttk.Button(root, text='更新信息',command=lambda: update_event()).grid(row=6, column=4)        # 查找学员        search_listbox = Listbox(root, height=3)        for item in ['按学号查找', '按姓名查找', '按年龄查找']:            search_listbox.insert(END, item)        search_listbox.grid(row=0, column=6, rowspan=3)        search_label = ttk.Label(root, text='查找参数').grid(row=3, column=5)        search_entry = ttk.Entry(root)        search_entry.grid(row=3, column=6)        search_button = ttk.Button(root, text='查找', command=lambda: search_event()).grid(row=5, column=6)        delete_button = ttk.Button(root, text='删除该学员', command=lambda: delete_event()).grid(row=6, column=6)        # 排序        sort_button_1 = ttk.Button(root, text='按学号排序', command=lambda: sort_event(1)).grid(row=1, column=7)        sort_button_1 = ttk.Button(root, text='按姓名排序', command=lambda: sort_event(2)).grid(row=2, column=7)        sort_button_1 = ttk.Button(root, text='按年龄排序', command=lambda: sort_event(3)).grid(row=3, column=7)        # 信息提示框        info_label = ttk.Label(root, text="信息展示窗口", background='#66ccff', width=100, anchor='center') \            .grid(row=7, column=0, columnspan=8)        # 信息展示        Listbox(root, height=8, width=110).grid(row=8, column=0, columnspan=10)        # 选择函数， 直接用SQL进行排序        def sort_event(n):            # 连接数据库            conn_1 = Mysql_conn()            if n == 1:                # 构造查询SQL                sw = 'SELECT * FROM STUDENT ORDER BY ID'                stu_info = conn_1.select(sw)                show_listbox = Listbox(root, height=8, width=110)                for row in stu_info:                    show_listbox.insert(END, row)                show_listbox.grid(row=8, column=0, columnspan=10)                messagebox.showinfo("排序", "已将学员按学号排序！")            elif n == 2:                # 构造查询SQL                sw = 'SELECT * FROM STUDENT ORDER BY NAME'                stu_info = conn_1.select(sw)                show_listbox = Listbox(root, height=8, width=110)                for row in stu_info:                    show_listbox.insert(END, row)                show_listbox.grid(row=8, column=0, columnspan=10)                messagebox.showinfo("排序", "已将学员按姓名排序！")            elif n == 3:                # 构造查询SQL                sw = 'SELECT * FROM STUDENT ORDER BY AGE'                stu_info = conn_1.select(sw)                show_listbox = Listbox(root, height=8, width=110)                for row in stu_info:                    show_listbox.insert(END, row)                show_listbox.grid(row=8, column=0, columnspan=10)                messagebox.showinfo("排序", "已将学员按年龄排序！")            # 关闭数据库连接            conn_1.close_conn()        # 提交学员信息        def upload_event():            i = []            # 连接数据库            conn_1 = Mysql_conn()            # root.update()            i.append(upload_entry_1.get())            i.append(upload_entry_2.get())            i.append(upload_entry_3.get())            i.append(upload_entry_4.get())            i.append(upload_entry_5.get())            # 清除输入框中的数据            upload_entry_1.delete(0, END)            upload_entry_2.delete(0, END)            upload_entry_3.delete(0, END)            upload_entry_4.delete(0, END)            upload_entry_5.delete(0, END)            # 构造SQL语句            uw = "INSERT INTO STUDENT (NAME, AGE, TEL_NUMBER, DATE, EMAIL)" \                 "VALUES('%s', '%s', '%s', '%s', '%s')" %(i[0], i[1], i[2], i[3], i[4])            conn_1.insert(uw)            messagebox.showinfo("保存提示", "已保存学员信息！")            # 刷新信息区            sw = 'SELECT * FROM STUDENT ORDER BY ID'            stu_info = conn_1.select(sw)            show_listbox = Listbox(root, height=8, width=110)            for row in stu_info:                show_listbox.insert(END, row)            show_listbox.grid(row=8, column=0, columnspan=10)            # 关闭数据库连接            conn_1.close_conn()        # 更新学员信息        def update_event():            i = []            # 连接数据库            conn_1 = Mysql_conn()            i.append(update_entry_1.get())            i.append(update_entry_2.get())            i.append(update_entry_3.get())            i.append(update_entry_4.get())            i.append(update_entry_5.get())            i.append(update_entry_6.get())            # 清除输入框中的数据            update_entry_1.delete(0, END)            update_entry_2.delete(0, END)            update_entry_3.delete(0, END)            update_entry_4.delete(0, END)            update_entry_5.delete(0, END)            update_entry_6.delete(0, END)            # 构造SQL语句            uw = "UPDATE STUDENT SET NAME = '%s', AGE = '%s', TEL_NUMBER = '%s', DATE = '%s', EMAIL = '%s' WHERE " \                 "ID = '%s'"% (i[1], i[2], i[3], i[4], i[5], i[0])            conn_1.update(uw)            messagebox.showinfo("更新提示", "已更新学员信息！")            # 刷新信息区            sw = 'SELECT * FROM STUDENT ORDER BY ID'            stu_info = conn_1.select(sw)            show_listbox = Listbox(root, height=8, width=110)            for row in stu_info:                show_listbox.insert(END, row)            show_listbox.grid(row=8, column=0, columnspan=10)            # 关闭数据库连接            conn_1.close_conn()        # 保存当前首位符合条件的学员的ID        cur_search_id = None        def search_event():            # 连接数据库            conn_1 = Mysql_conn()            # 构造SQL语句            sw = 'SELECT * FROM STUDENT ORDER BY ID'            stu_info = conn_1.select(sw)            # 保存当前首位符合条件的学员的ID            global cur_search_id            cur_search_id = stu_info[0][0]            for items in stu_info:                node = []                node.append(items[0])                node.append(items[1])                node.append(items[2])                node.append(items[3])                node.append(items[4])                node.append(items[5])                self.dl.add(node)            key = search_listbox.curselection()            value = search_entry.get()            # 删除搜索框中数据            search_entry.delete(0, END)            results = self.dl.find(value, key[0])            show_listbox = Listbox(root, height=8, width=110)            for row in results:                show_listbox.insert(END, row)            show_listbox.grid(row=8, column=0, columnspan=10)            # 清空链表            self.dl.release()            # 关闭数据库连接            conn_1.close_conn()        def delete_event():            # 连接数据库            conn_1 = Mysql_conn()            global cur_search_id            messagebox.showinfo("删除提示", "该学员信息已删除！")            # 从数据库中删除该学员，以保持同步            rw = "DELETE FROM STUDENT WHERE ID = '%d'" % (cur_search_id)            conn_1.delete(rw)            # 将cur_search_id 置为 None，防止误删            cur_search_id = None            # 断开数据库            conn_1.close_conn()            # 刷新数据显示            Listbox(root, height=8, width=110).grid(row=8, column=0, columnspan=10)root = Tk()test = GUI(root)root.mainloop()