Tkinter Entry数据获取与二进制文件保存：按钮命令回调机制详解

save_button = tk.Button(root, command=save_key_to_file, text="Save Key", ...)

# 假设 save_key_to_file 函数需要一个文件名参数
# def save_key_to_file(filename): ...
save_button = tk.Button(root, command=lambda: save_key_to_file('custom_file.key'), text="Save Key", ...)

def save_key_to_file():
    key_string = key_entry.get()  # 获取Entry中的字符串
    if not key_string:
        print("Entry is empty, no key to save.")
        return

    # 将字符串编码为字节序列（例如UTF-8），以便写入二进制文件
    key_bytes = key_string.encode('utf-8')

    # 打印以验证获取到的内容和编码后的字节
    print(f"Retrieved key string: {key_string}")
    print(f"Encoded key bytes: {key_bytes}")

    try:
        with open("file.key", "wb") as file:
            file.write(key_bytes)
        print("Key successfully saved to file.key")
    except IOError as e:
        print(f"Error saving key to file: {e}")

import tkinter as tk
from tkinter import filedialog # 尽管原始代码未使用，但通常用于文件对话框
from cryptography.fernet import Fernet # 用于生成密钥
import os # 尽管原始代码未使用，但通常用于文件操作

def generate_key():
    """生成一个新的Fernet密钥并显示在Entry中。"""
    key = Fernet.generate_key()
    key_entry.delete(0, tk.END) # 清空Entry
    key_entry.insert(0, key.decode('utf-8')) # 将字节密钥解码为字符串显示

def save_key_to_file():
    """从Entry获取密钥并保存到二进制文件。"""
    key_string = key_entry.get()
    if not key_string:
        print("Entry is empty, no key to save.")
        return

    # 将字符串密钥编码为字节序列
    try:
        key_bytes = key_string.encode('utf-8')
    except UnicodeEncodeError as e:
        print(f"Error encoding key: {e}")
        return

    # 将字节密钥写入二进制文件
    try:
        with open("file.key", "wb") as file:
            file.write(key_bytes)
        print(f"Key successfully saved to file: {os.path.abspath('file.key')}")
    except IOError as e:
        print(f"Error saving key to file: {e}")

def load_key_from_file():
    """从二进制文件加载密钥并显示在Entry中。"""
    try:
        with open("file.key", "rb") as file:
            key_bytes = file.read()
            key_entry.delete(0, tk.END)
            key_entry.insert(0, key_bytes.decode('utf-8')) # 将字节密钥解码为字符串显示
            print(f"Key loaded from file: {os.path.abspath('file.key')}")
    except FileNotFoundError:
        print("file.key not found.")
    except UnicodeDecodeError as e:
        print(f"Error decoding key from file: {e}")
    except IOError as e:
        print(f"Error loading key from file: {e}")


# 初始化Tkinter主窗口
root = tk.Tk()
root.title("密钥管理工具")
root.geometry("450x200")
root.configure(bg="lightgray")

# 密钥输入框
key_label = tk.Label(root, text="密钥:", bg="lightgray", fg="black")
key_label.place(x=35, y=70)
key_entry = tk.Entry(root, bg="grey", fg="green", width=50)
key_entry.place(x=35, y=100)

# 生成密钥按钮
generate_button = tk.Button(root, text="生成密钥", borderwidth=0, bg="black", fg="green",
                            activebackground='#2e2e2e', activeforeground="green",
                            command=generate_key) # 正确绑定：传递函数引用
generate_button.place(x=35, y=130)

# 保存密钥按钮
save_button = tk.Button(root, text="保存密钥", borderwidth=0, bg="black", fg="green",
                        activebackground='#2e2e2e', activeforeground="green",
                        command=save_key_to_file) # 正确绑定：传递函数引用
save_button.place(x=150, y=130)

# 加载密钥按钮
load_button = tk.Button(root, text="加载密钥", borderwidth=0, bg="black", fg="green",
                        activebackground='#2e2e2e', activeforeground="green",
                        command=load_key_from_file) # 正确绑定：传递函数引用
load_button.place(x=270, y=130)


# 启动Tkinter事件循环
root.mainloop()