Python计算器 Python实现的简单计算器功能详解

class CalcFrame(wx.Frame):#建造一个继承于wx.Frame的frame
  def __init__(self,title):
    wx.Frame.__init__ (self,None,-1,title,
              pos=(100,300),size=(300,320))
    panel=wx.Panel(self)
    boxsize=wx.BoxSizer(wx.VERTICAL)
    gridBox=wx.GridSizer(4,4,1,1)
    self.equation=""#记录一个等式，把它print到TextCtrl中

    self.textprint=wx.TextCtrl(panel,-1,'',style=wx.TE_RIGHT|wx.TE_READONLY)#文本控制控件
    self.bgFont=wx.Font(25,wx.SWISS,wx.NORMAL,wx.BOLD,face=u'Roboto')#设置字体样式
    self.textprint.SetFont(self.bgFont)#使用SetFont将设置的字体样式运用在textprint中
    self.textprint.SetForegroundColour('black')#设置前景色
    self.textprint.SetBackgroundColour('white')#设置后景色

    self.buttonData="7 8 9 DEL 4 5 6 AC 1 2 3 * / + - =".split()
    #产生buttonIterm的label
    #将label分配到按钮上去
    buttonLength=len(self.buttonData)
    for i in range(buttonLength):
      labels="%s" %self.buttonData[i]
      buttonIterm = wx.Button(panel,i,labels)
      self.createHandler(buttonIterm,labels)
      gridBox.Add(buttonIterm,0,flag=wx.EXPAND)

    boxsize.Add(self.textprint,1,flag=wx.EXPAND)#在boxsize中加上文本控制控件，比例为1
    boxsize.Add(gridBox,5,flag=wx.EXPAND)
    panel.SetSizerAndFit(boxsize)#将boxsize放入panel里

  def createHandler(self,button,labels):
    #self.Bind(wx.EVT_BUTTON, self.OnButton1, self.Button1)
    #这里self是一个Frame（wxPython中的窗体这样的东西），而Button1是放在这个Frame下面的一个Button，self.OnButton1就是事件处理函数。而wxPython定死了事件处理函数的形式：
    items="DEL AC ="
    if labels not in items:
      self.Bind(wx.EVT_BUTTON,self.OnAppend,button)
    elif labels=='DEL':
      self.Bind(wx.EVT_BUTTON,self.OnDel,button)
    elif labels=='AC':
      self.Bind(wx.EVT_BUTTON,self.OnAc,button)
    elif labels=='=':
      self.Bind(wx.EVT_BUTTON,self.OnEqual,button)

  def OnAppend(self,event):
    eventbutton = event.GetEventObject()
    label = eventbutton.GetLabel()
    self.equation += label
    self.textprint.SetValue(self.equation)
  def OnDel(self,event):
    self.equation=self.equation[:-1]
    self.textprint.SetValue(self.equation)
  def OnAc(self,event):
    self.textprint.Clear()
    self.equation=""
  def OnEqual(self,event):
    string=self.equation
    try:
      taget=eval(string)#执行这段代码得到的结果
      self.equation=str(taget)
      self.textprint.SetValue(self.equation)
    except SyntaxError:#弹出消息对话框
      dlg=wx.MessageDialog(self,u'输入格式错误',wx.Ok|wx.ICON_INFORMATION)
      dlg.ShowModal()
      dlg.Destory()

class App(wx.App):
  def OnInit(self):
    self.frame =CalcFrame(u'计算器')
    self.frame.Center()
    self.frame.Show()
    return True

if __name__=="__main__":
  app=App()
  app.MainLoop()

# -*- coding:utf-8 -*-
'''
Created on 2018年8月25日
@author: Administrator
'''
import wx
class CalcFrame(wx.Frame):#建造一个继承于wx.Frame的frame
  def __init__(self,title):
    wx.Frame.__init__ (self,None,-1,title,
              pos=(100,300),size=(300,320))
    panel=wx.Panel(self)
    boxsize=wx.BoxSizer(wx.VERTICAL)
    gridBox=wx.GridSizer(4,4,1,1)
    self.equation=""#记录一个等式，把它print到TextCtrl中
    self.textprint=wx.TextCtrl(panel,-1,'',style=wx.TE_RIGHT|wx.TE_READONLY)#文本控制控件
    self.bgFont=wx.Font(25,wx.SWISS,wx.NORMAL,wx.BOLD,face=u'Roboto')#设置字体样式
    self.textprint.SetFont(self.bgFont)#使用SetFont将设置的字体样式运用在textprint中
    self.textprint.SetForegroundColour('black')#设置前景色
    self.textprint.SetBackgroundColour('white')#设置后景色
    self.buttonData="7 8 9 DEL 4 5 6 AC 1 2 3 * / + - =".split()
    #产生buttonIterm的label
    #将label分配到按钮上去
    buttonLength=len(self.buttonData)
    for i in range(buttonLength):
      labels="%s" %self.buttonData[i]
      buttonIterm = wx.Button(panel,i,labels)
      self.createHandler(buttonIterm,labels)
      gridBox.Add(buttonIterm,0,flag=wx.EXPAND)
    boxsize.Add(self.textprint,1,flag=wx.EXPAND)#在boxsize中加上文本控制控件，比例为1
    boxsize.Add(gridBox,5,flag=wx.EXPAND)
    panel.SetSizerAndFit(boxsize)#将boxsize放入panel里
  def createHandler(self,button,labels):
    #self.Bind(wx.EVT_BUTTON, self.OnButton1, self.Button1)
    #这里self是一个Frame（wxPython中的窗体这样的东西），而Button1是放在这个Frame下面的一个Button，self.OnButton1就是事件处理函数。而wxPython定死了事件处理函数的形式：
    items="DEL AC ="
    if labels not in items:
      self.Bind(wx.EVT_BUTTON,self.OnAppend,button)
    elif labels=='DEL':
      self.Bind(wx.EVT_BUTTON,self.OnDel,button)
    elif labels=='AC':
      self.Bind(wx.EVT_BUTTON,self.OnAc,button)
    elif labels=='=':
      self.Bind(wx.EVT_BUTTON,self.OnEqual,button)
  def OnAppend(self,event):
    eventbutton = event.GetEventObject()
    label = eventbutton.GetLabel()
    self.equation += label
    self.textprint.SetValue(self.equation)
  def OnDel(self,event):
    self.equation=self.equation[:-1]
    self.textprint.SetValue(self.equation)
  def OnAc(self,event):
    self.textprint.Clear()
    self.equation=""
  def OnEqual(self,event):
    string=self.equation
    try:
      taget=eval(string)#执行这段代码得到的结果
      self.equation=str(taget)
      self.textprint.SetValue(self.equation)
    except SyntaxError:#弹出消息对话框
      dlg=wx.MessageDialog(self,u'输入格式错误',wx.Ok|wx.ICON_INFORMATION)
      dlg.ShowModal()
      dlg.Destory()
class App(wx.App):
  def OnInit(self):
    self.frame =CalcFrame(u'计算器')
    self.frame.Center()
    self.frame.Show()
    return True
if __name__=="__main__":
  app=App()
  app.MainLoop()