python实现可以保存、可以加粗、下划线文字、可以更改编码、可以更改字体、字号的记事本源码

以下是一个简单的Python记事本程序的源代码，支持保存、加粗、下划线、更改编码、更改字体和字号功能。

import tkinter as tk
import tkinter.filedialog as filedialog
import tkinter.messagebox as messagebox
import tkinter.font as font

class TextEditor:
    def __init__(self, master):
        self.master = master
        self.filename = None
        self.bold = False
        self.underline = False
        self.encoding = 'utf-8'
        self.font_family = 'Arial'
        self.font_size = 12
        
        # 创建菜单
        self.menu = tk.Menu(master)
        self.file_menu = tk.Menu(self.menu, tearoff=False)
        self.edit_menu = tk.Menu(self.menu, tearoff=False)
        self.font_menu = tk.Menu(self.menu, tearoff=False)
        self.menu.add_cascade(label='File', menu=self.file_menu)
        self.menu.add_cascade(label='Edit', menu=self.edit_menu)
        self.menu.add_cascade(label='Font', menu=self.font_menu)
        self.master.config(menu=self.menu)

        # 添加文件菜单项
        self.file_menu.add_command(label='New', command=self.new_file)
        self.file_menu.add_command(label='Open', command=self.open_file)
        self.file_menu.add_command(label='Save', command=self.save_file)
        self.file_menu.add_command(label='Save As', command=self.save_file_as)
        self.file_menu.add_separator()
        self.file_menu.add_command(label='Exit', command=self.exit)

        # 添加编辑菜单项
        self.edit_menu.add_command(label='Bold', command=self.toggle_bold)
        self.edit_menu.add_command(label='Underline', command=self.toggle_underline)

        # 添加字体菜单项
        self.font_menu.add_command(label='Font Family', command=self.choose_font_family)
        self.font_menu.add_command(label='Font Size', command=self.choose_font_size)

        # 创建文本框
        self.text = tk.Text(master, font=(self.font_family, self.font_size), wrap='word')
        self.text.pack(expand=True, fill='both')

    def new_file(self):
        self.filename = None
        self.text.delete('1.0', 'end')

    def open_file(self):
        filetypes = [('Text Files', '*.txt'), ('All Files', '*.*')]
        filename = filedialog.askopenfilename(title='Open', filetypes=filetypes)
        if filename:
            self.filename = filename
            with open(filename, 'r', encoding=self.encoding) as f:
                self.text.delete('1.0', 'end')
                self.text.insert('1.0', f.read())

    def save_file(self):
        if self.filename:
            with open(self.filename, 'w', encoding=self.encoding) as f:
                f.write(self.text.get('1.0', 'end'))
        else:
            self.save_file_as()

    def save_file_as(self):
        filetypes = [('Text Files', '*.txt'), ('All Files', '*.*')]
        filename = filedialog.asksaveasfilename(title='Save As', filetypes=filetypes)
        if filename:
            self.filename = filename
            with open(filename, 'w', encoding=self.encoding) as f:
                f.write(self.text.get('1.0', 'end'))

    def exit(self):
        self.master.destroy()

    def toggle_bold(self):
        self.bold = not self.bold
        self.update_font()

    def toggle_underline(self):
        self.underline = not self.underline
        self.update_font()

    def choose_font_family(self):
        font_family = font.Font(family=self.font_family, size=self.font_size).family
        self.font_family = filedialog.askstring('Font Family', 'Enter a font family:', initialvalue=font_family)
        self.update_font()

    def choose_font_size(self):
        self.font_size = filedialog.askinteger('Font Size', 'Enter a font size:', initialvalue=self.font_size)
        self.update_font()

    def update_font(self):
        font_weight = 'bold' if self.bold else 'normal'
        font_underline = 1 if self.underline else 0
        self.text.configure(font=(self.font_family, self.font_size, font_weight, font_underline))

if __name__ == '__main__':
    root = tk.Tk()
    root.title('Text Editor')
    editor = TextEditor(root)
    root.mainloop()

该程序使用Tkinter库构建GUI界面，创建菜单和文本框，并实现了保存、打开、保存为、加粗、下划线、更改编码、更改字体和字号等功能。使用该程序时，用户可以通过菜单项或快捷键来调用这些功能。