Python实现简易计算器的示例代码

Tkinter作为 Python GUI 开发工具之一，它具有 GUI 软件包的必备的常用功能。本文就将利用Tkinter编写简易的计算器，感兴趣的可以了解一下

实现流程

1.计算机布局

2.计算机执行

首先导入模块:

Tkinter 作为 Python GUI 开发工具之一，它具有 GUI 软件包的必备的常用功能。比如，它提供了十多种不同类型的窗口控件、窗口布局管理器、事件处理机制等，加之其开发效率高、代码简洁易读

import tkinter as tk #Python3标准安装包中自带tkinter，即不用安装，导入即可使用。 #可以从命令行运行python -m tkinter会打开一个窗口 #演示一个简单的Tk接口，证明tkinter已正确安装在系统上. #python -m tkinter

计算器布局

1、先完成整个计算机的布局及其它输出结果的一栏

前面完成整体布局就细化计算器中的按钮

1、前四行代码是定义按钮的符号、长宽、字体、颜色

2、后四行是按钮的间距

root = tk.Tk() root.title('计算器') root.geometry('295x280+100+100') #边距 font = ('宋体', 20) font_16 = ('宋体', 16) root.attributes("-alpha", 0.9) #设置透明度 result_num = tk.StringVar() #赋予可变变量 result_num.set('') tk.Label(root, textvariable=result_num, font=font, height=2, width=20, justify=tk.LEFT, anchor=tk.SE ).grid(row=1, column=1, columnspan=4) #显示结果的布局 button_clear = tk.Button(root, text='C', width=5, font=font_16, relief=tk.FLAT, bg='#b1b2b2') #定义按钮的符号、长宽、字体、颜色 button_back = tk.Button(root, text='←', width=5, font=font_16, relief=tk.FLAT, bg='#b1b2b2') #定义按钮的符号、长宽、字体、颜色 button_division = tk.Button(root, text='÷', width=5, font=font_16, relief=tk.FLAT, bg='#b1b2b2') #定义按钮的符号、长宽、字体、颜色 button_multiplication = tk.Button(root, text='×', width=5, font=font_16, relief=tk.FLAT, bg='#b1b2b2') #定义按钮的符号、长宽、字体、颜色 button_clear.grid(row=2, column=1, padx=4, pady=2) button_back.grid(row=2, column=2, padx=4, pady=2) button_division.grid(row=2, column=3, padx=4, pady=2) button_multiplication.grid(row=2, column=4, padx=4, pady=2) #定义按钮位置 #依葫芦画瓢 button_seven = tk.Button(root, text='7', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_eight = tk.Button(root, text='8', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_nine = tk.Button(root, text='9', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_subtraction = tk.Button(root, text='-', width=5, font=font_16, relief=tk.FLAT, bg='#b1b2b2') button_seven.grid(row=3, column=1, padx=4, pady=2) button_eight.grid(row=3, column=2, padx=4, pady=2) button_nine.grid(row=3, column=3, padx=4, pady=2) button_subtraction.grid(row=3, column=4, padx=4, pady=2) #依葫芦画瓢 button_four = tk.Button(root, text='4', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_five = tk.Button(root, text='5', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_six = tk.Button(root, text='6', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_addition = tk.Button(root, text='+', width=5, font=font_16, relief=tk.FLAT, bg='#b1b2b2') button_four.grid(row=4, column=1, padx=4, pady=2) button_five.grid(row=4, column=2, padx=4, pady=2) button_six.grid(row=4, column=3, padx=4, pady=2) button_addition.grid(row=4, column=4, padx=4, pady=2) #依葫芦画瓢 button_one = tk.Button(root, text='1', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_two = tk.Button(root, text='2', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_three = tk.Button(root, text='3', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_equal = tk.Button(root, text='=', width=5, font=font_16, relief=tk.FLAT, bg='#b1b2b2') button_one.grid(row=5, column=1, padx=4, pady=2) button_two.grid(row=5, column=2, padx=4, pady=2) button_three.grid(row=5, column=3, padx=4, pady=2) button_equal.grid(row=5, column=4, padx=4, pady=2) button_zero1 = tk.Button(root, text=' ', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_zero = tk.Button(root, text='0', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_dot = tk.Button(root, text='.', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_equal2 = tk.Button(root, text=' ', width=5, font=font_16, relief=tk.FLAT, bg='#b1b2b2') button_zero1.grid(row=6, column=1, padx=4, pady=2) button_zero.grid(row=6, column=2, padx=4, pady=2) button_dot.grid(row=6, column=3, padx=4, pady=2) button_equal2.grid(row=6, column=4, padx=4, pady=2)

计算机执行

计算器布局完成后（主体和细节）赋予计算器计算能力

1、点击按钮实现出现结果输出栏及计算器的输出栏

2、赋予事件能力

def click_button(x): print('X:\t', x) result_num.set(result_num.get() + x)

点击按钮可以输入所对应的结果并且调用lambda函数计算输入结果并反馈

ambda 函数是匿名的：所谓匿名函数，通俗地说就是没有名字的函数。lambda函数没有名字。 lambda 函数有输入和输出：输入是传入到参数列表argument_list的值，输出是根据表达式expression计算得到的值。

button_one.config(command=lambda: click_button('1')) button_two.config(command=lambda: click_button('2')) button_three.config(command=lambda: click_button('3')) button_four.config(command=lambda: click_button('4')) button_five.config(command=lambda: click_button('5')) button_six.config(command=lambda: click_button('6')) button_seven.config(command=lambda: click_button('7')) button_eight.config(command=lambda: click_button('8')) button_nine.config(command=lambda: click_button('9')) button_zero.config(command=lambda: click_button('0')) button_dot.config(command=lambda: click_button('.')) button_addition.config(command=lambda: click_button('+')) button_subtraction.config(command=lambda: click_button('-')) button_multiplication.config(command=lambda: click_button('*')) button_division.config(command=lambda: click_button('/')) button_clear.config(command=lambda: btnClearDisplay()) button_equal.config(command=calculation)

调用calculation时间用来计算输入结果其中str来转化字符串.

调用btnClearDisplay清除来清空输入结果

def calculation(): opt_str = result_num.get() result = eval(opt_str) result_num.set(str(result)) def btnClearDisplay(): opt_str = result_num.get() result = eval(str(opt_str)) result_num.set("")

最后一行代码不需要触发lambda 因为不需要匿名函数也不用传递参数

button_clear.config(command=lambda: btnClearDisplay()) button_equal.config(command=calculation)

代码展示

import tkinter as tk root = tk.Tk() root.title('计算器') root.geometry('295x280+100+100') font = ('宋体', 20) font_16 = ('宋体', 16) root.attributes("-alpha", 0.9) result_num = tk.StringVar() result_num.set('') tk.Label(root, textvariable=result_num, font=font, height=2, width=20, justify=tk.LEFT, anchor=tk.SE ).grid(row=1, column=1, columnspan=4) button_clear = tk.Button(root, text='C', width=5, font=font_16, relief=tk.FLAT, bg='#b1b2b2') button_back = tk.Button(root, text='←', width=5, font=font_16, relief=tk.FLAT, bg='#b1b2b2') button_division = tk.Button(root, text='÷', width=5, font=font_16, relief=tk.FLAT, bg='#b1b2b2') button_multiplication = tk.Button(root, text='×', width=5, font=font_16, relief=tk.FLAT, bg='#b1b2b2') button_clear.grid(row=2, column=1, padx=4, pady=2) button_back.grid(row=2, column=2, padx=4, pady=2) button_division.grid(row=2, column=3, padx=4, pady=2) button_multiplication.grid(row=2, column=4, padx=4, pady=2) button_seven = tk.Button(root, text='7', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_eight = tk.Button(root, text='8', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_nine = tk.Button(root, text='9', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_subtraction = tk.Button(root, text='-', width=5, font=font_16, relief=tk.FLAT, bg='#b1b2b2') button_seven.grid(row=3, column=1, padx=4, pady=2) button_eight.grid(row=3, column=2, padx=4, pady=2) button_nine.grid(row=3, column=3, padx=4, pady=2) button_subtraction.grid(row=3, column=4, padx=4, pady=2) button_four = tk.Button(root, text='4', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_five = tk.Button(root, text='5', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_six = tk.Button(root, text='6', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_addition = tk.Button(root, text='+', width=5, font=font_16, relief=tk.FLAT, bg='#b1b2b2') button_four.grid(row=4, column=1, padx=4, pady=2) button_five.grid(row=4, column=2, padx=4, pady=2) button_six.grid(row=4, column=3, padx=4, pady=2) button_addition.grid(row=4, column=4, padx=4, pady=2) button_one = tk.Button(root, text='1', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_two = tk.Button(root, text='2', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_three = tk.Button(root, text='3', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_equal = tk.Button(root, text='=', width=5, font=font_16, relief=tk.FLAT, bg='#b1b2b2') button_one.grid(row=5, column=1, padx=4, pady=2) button_two.grid(row=5, column=2, padx=4, pady=2) button_three.grid(row=5, column=3, padx=4, pady=2) button_equal.grid(row=5, column=4, padx=4, pady=2) button_zero1 = tk.Button(root, text=' ', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_zero = tk.Button(root, text='0', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_dot = tk.Button(root, text='.', width=5, font=font_16, relief=tk.FLAT, bg='#eacda1') button_equal2 = tk.Button(root, text=' ', width=5, font=font_16, relief=tk.FLAT, bg='#b1b2b2') button_zero1.grid(row=6, column=1, padx=4, pady=2) button_zero.grid(row=6, column=2, padx=4, pady=2) button_dot.grid(row=6, column=3, padx=4, pady=2) button_equal2.grid(row=6, column=4, padx=4, pady=2) def click_button(x): print('X:\t', x) result_num.set(result_num.get() + x) def calculation(): opt_str = result_num.get() result = eval(opt_str) result_num.set(str(result)) def btnClearDisplay(): opt_str = result_num.get() result = eval(str(opt_str)) result_num.set("") button_one.config(command=lambda: click_button('1')) button_two.config(command=lambda: click_button('2')) button_three.config(command=lambda: click_button('3')) button_four.config(command=lambda: click_button('4')) button_five.config(command=lambda: click_button('5')) button_six.config(command=lambda: click_button('6')) button_seven.config(command=lambda: click_button('7')) button_eight.config(command=lambda: click_button('8')) button_nine.config(command=lambda: click_button('9')) button_zero.config(command=lambda: click_button('0')) button_dot.config(command=lambda: click_button('.')) button_addition.config(command=lambda: click_button('+')) button_subtraction.config(command=lambda: click_button('-')) button_multiplication.config(command=lambda: click_button('*')) button_division.config(command=lambda: click_button('/')) button_clear.config(command=lambda: btnClearDisplay()) button_equal.config(command=calculation) root.mainloop()