python GUI模拟实现计算器

python编写计算器，供大家参考，具体内容如下

（1）计算器界面如下：

（2）基本满足了计算器的所有需求，使用时不可键盘输入，只能鼠标点击左键才可执行。初始时显示0.0，每次输入的内容存于D:num.txt(启动程序时自动创建)

（3）" AC " 记录清零返回初始 0.0；" delete " 删除上一个输入内容；" +/- " 将正数为负数，负数为正数

（4）对于不同的进制数值系统，小数的精准值不同。
因此计算机会出现 0.1+0.2=0.3000000000004 的现象
能对数据进行截断处理，可以解决问题，但精度丧失。
（此计算机没有进行截断处理）

import tkinter,osfrom tkinter import *def temp(string):#空白间隔  temp=tkinter.Frame(string,width=20,height=50)  temp.pack()flag=0node=0def num_work():   #更新显示框Lable  global flag  global node  with open("D:num.txt") as f:    for length in f:      string=length  top_work.configure(text=string.strip('n'))  # 重新设置标签文本  root.after(500,num_work) # 每隔0.5s调用函数num_work自身获取结果def num_math_int(num1,num2):#整数运算  try:    if num2[0]=='+':      string=int(num1)+int(num2[1:])    elif num2[0]=='-':      string=int(num1)-int(num2[1:])    elif num2[0]=='x':      string=int(num1)*int(num2[1:])    elif num2[0]=='/':      string=int(num1)/int(num2[1:])          with open("D:num.txt",'a') as f:      f.write('n'+str(string)+'n')  except:    with open("D:num.txt",'a') as f:        f.write('n错误')def num_math_float(num1,num2):#小数运算  try:    if num2[0]=='+':      string=float(num1)+float(num2[1:])    elif num2[0]=='-':      string=float(num1)-float(num2[1:])    elif num2[0]=='x':      string=float(num1)*float(num2[1:])    elif num2[0]=='/':      string=float(num1)/float(num2[1:])    if flag==0:      with open("D:num.txt",'a') as f:        f.write('n'+str(string)+'n')    else:      with open("D:num.txt",'a') as f:        f.write('n'+str(string))  except:    with open("D:num.txt",'a') as f:        f.write('n错误')def decimal(num):  if num.count('%')>0:    num=num.replace('%','')    num=num.replace('n','')    if num.isnumeric():      num=str(float(num)/100)    else:      num=num[0]+str(float(num[1:])/100)  return num    def work(string):#按键对应的功能  if string.isnumeric():    with open("D:num.txt","a") as file:      file.write(string)  else:    #读取文件D:num.txt所有内容    lists=[]    with open("D:num.txt","r") as file:      for length in file:        lists.append(length)              if string=='AC':      with open("D:num.txt","w") as file:        file.write('0.0n')            elif string=='=':      num1=lists[-2]      num2=lists[-1]      if num1=='n':#解决末尾为换行的情况        num1=lists[-3]              #将百分数小数化      #出现结果多0.0000000001      num1=decimal(num1)      num2=decimal(num2)              try:      #判断两个数是整数还是小数        number=int(num1)        number=int(num2[1:])        num_math_int(num1,num2)#两个数进行整数运算      except:        num_math_float(num1,num2)#两个数进行小数运算            elif string=='.':      if lists[-1].count('.')==0:#判断结尾是否有小数点，没有写入否则报错        with open("D:num.txt","a") as file:          file.write(string)      else:        with open("D:num.txt","a") as file:          file.write('n错误')              elif string=='+/-':      if lists[-1].count('-')==0:#-+为-        if lists[-1].count('+')==1:          lists[-1]=lists[-1].replace('+','')        lists[-1]='-'+lists[-1]      else:           #--为+        lists[-1]=lists[-1].replace('-','+')      #更新文件      with open("D:num.txt","w") as file:        pass      for length in lists:        with open("D:num.txt","a") as file:          file.write(length)              elif string=='delete':      number=lists[-1]      lists[-1]=number[0:(len(number)-1)]#删除一位      #更新文件      with open("D:num.txt","w") as file:        pass      for length in lists:        with open("D:num.txt","a") as file:          file.write(length)    elif string=='%':      if lists[-1].endswith("%")==False:        with open("D:num.txt","a") as file:          file.write(string)      else:        with open("D:num.txt","a") as file:          file.write('n错误')          else:      with open("D:num.txt","a") as file:        file.write('n'+string)  def run():#计算器显示界面主体    if os.path.exists("D:num.txt")==False:    with open("D:num.txt",'w') as f:      f.write('0.0n')        global root#定义全局变量root,方便Label更新  root=tkinter.Tk()  root.title("计算器")    #x = root.winfo_screenwidth()  #获取当前屏幕的宽  #y = root.winfo_screenheight()  #获取当前屏幕的高  #print(((x-500)//2),((y-600)//2))#为居中提供的参数    root.geometry('400x500+760+290')#主体长400，高500，居中  top=tkinter.Frame(root,width=20,height=50)  top.pack()  global top_work#定义全局变量root  temp(top)#空白间隔  #计算器显示框  top_work=tkinter.Label(top,text='',justify='left',relief=SUNKEN,bd=10,bg='white',width=40)  top_work.pack(side='bottom')#计算器显示框（位置居下）  num_work()  temp(root)#空白间隔    number=tkinter.Frame(root)#成放计算机键盘的容器  number.pack()  #所有按键，AC键为事例  numberAC=tkinter.Button(number,text="AC",width=10,command=lambda : work('AC')).grid(row=0,column=0)  #左键点击，执行函数work  #按键位置（0,0）    numberdelete=tkinter.Button(number,text="delete",width=10,command=lambda : work('delete')).grid(row=0,column=1)  numberzhengfu=tkinter.Button(number,text="+/-",width=10,command=lambda : work('+/-')).grid(row=0,column=2)  numberchu=tkinter.Button(number,text="/",width=10,command=lambda : work('/')).grid(row=0,column=3)    tkinter.Button(number,text="7",width=10,command=lambda : work('7')).grid(row=1,column=0)  tkinter.Button(number,text="8",width=10,command=lambda : work('8')).grid(row=1,column=1)  tkinter.Button(number,text="9",width=10,command=lambda : work('9')).grid(row=1,column=2)  tkinter.Button(number,text="x",width=10,command=lambda : work('x')).grid(row=1,column=3)    tkinter.Button(number,text="4",width=10,command=lambda : work('4')).grid(row=2,column=0)  tkinter.Button(number,text="5",width=10,command=lambda : work('5')).grid(row=2,column=1)  tkinter.Button(number,text="6",width=10,command=lambda : work('6')).grid(row=2,column=2)  tkinter.Button(number,text="-",width=10,command=lambda : work('-')).grid(row=2,column=3)    tkinter.Button(number,text="1",width=10,command=lambda : work('1')).grid(row=3,column=0)  tkinter.Button(number,text="2",width=10,command=lambda : work('2')).grid(row=3,column=1)  tkinter.Button(number,text="3",width=10,command=lambda : work('3')).grid(row=3,column=2)  tkinter.Button(number,text="+",width=10,command=lambda : work('+')).grid(row=3,column=3)    tkinter.Button(number,text="%",width=10,command=lambda : work('%')).grid(row=4,column=0)  tkinter.Button(number,text="0",width=10,command=lambda : work('0')).grid(row=4,column=1)  tkinter.Button(number,text=".",width=10,command=lambda : work('.')).grid(row=4,column=2)  tkinter.Button(number,text="=",width=10,command=lambda : work('=')).grid(row=4,column=3)  root.mainloop()if __name__=='__main__':  run()

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持我们。