用python的tkinter库写个记事本

好的，以下是一个简单的用 Python 的 tkinter 库编写的记事本：

from tkinter import *
from tkinter.filedialog import asksaveasfilename, askopenfilename

# 创建主窗口
root = Tk()
root.title("记事本")

# 创建文本框
text = Text(root, font=("Helvetica", 12))
text.pack(expand=True, fill=BOTH)

# 创建菜单栏
menu_bar = Menu(root)
root.config(menu=menu_bar)

# 创建文件菜单
file_menu = Menu(menu_bar, tearoff=0)
menu_bar.add_cascade(label="文件", menu=file_menu)

# 打开文件
def open_file(event=None):
    file_path = askopenfilename(defaultextension=".txt", filetypes=[("Text Files", "*.txt"), ("All Files", "*.*")])
    if file_path:
        text.delete(1.0, END)
        with open(file_path, "r") as file:
            text.insert(END, file.read())

file_menu.add_command(label="打开", accelerator="Ctrl+O", command=open_file)

# 保存文件
def save_file(event=None):
    file_path = asksaveasfilename(defaultextension=".txt", filetypes=[("Text Files", "*.txt"), ("All Files", "*.*")])
    if file_path:
        with open(file_path, "w") as file:
            file.write(text.get(1.0, END))

file_menu.add_command(label="保存", accelerator="Ctrl+S", command=save_file)

# 退出
file_menu.add_separator()
file_menu.add_command(label="退出", accelerator="Alt+F4", command=root.quit)

# 创建编辑菜单
edit_menu = Menu(menu_bar, tearoff=0)
menu_bar.add_cascade(label="编辑", menu=edit_menu)

# 撤销
def undo(event=None):
    try:
        text.edit_undo()
    except:
        pass

edit_menu.add_command(label="撤销", accelerator="Ctrl+Z", command=undo)

# 重做
def redo(event=None):
    try:
        text.edit_redo()
    except:
        pass

edit_menu.add_command(label="重做", accelerator="Ctrl+Y", command=redo)

# 剪切
edit_menu.add_separator()
edit_menu.add_command(label="剪切", accelerator="Ctrl+X", command=lambda: text.event_generate("<Control-x>"))

# 复制
edit_menu.add_command(label="复制", accelerator="Ctrl+C", command=lambda: text.event_generate("<Control-c>"))

# 粘贴
edit_menu.add_command(label="粘贴", accelerator="Ctrl+V", command=lambda: text.event_generate("<Control-v>"))

# 删除
edit_menu.add_command(label="删除", accelerator="Del", command=lambda: text.delete("sel.first", "sel.last"))

# 全选
edit_menu.add_separator()
edit_menu.add_command(label="全选", accelerator="Ctrl+A", command=lambda: text.tag_add("sel", "1.0", "end"))

# 运行主循环
root.mainloop()

希望这个记事本对你有所帮助！