40行python代码编写的计算器详解编程语言

    from tkinter import *   
    reset=True   
    def buttonCallBack(event):   
        global label   
        global reset   
        num=event.widget['text']   
        if num=='C':   
            label['text']="0"   
            return   
        if num in "=":   
            label['text']=str(eval(label['text']))   
            reset=True   
            return    
        s=label['text']   
        if s=='0' or reset==True:   
            s=""   
            reset=False   
        label['text']=s+num   
    #主窗口   
    root=Tk()   
    root.wm_title("计算器")   
    #显示栏1   
    label=Label(root,text="0",background="white",anchor="e")   
    label['width']=35   
    label['height']=2   
    label.grid(row=1,columnspan=4,sticky=W)   
    #按钮   
    showText="789/456*123-0.C+"   
    for i in range(4):   
        for j in range(4):   
            b=Button(root,text=showText[i*4+j],width=7)   
            b.grid(row=i+2,column=j)   
            b.bind("<Button-1>",buttonCallBack)   
    showText="()"   
    for i in range(2):   
        b=Button(root,text=showText[i],width=7)   
        b.grid(row=6,column=2+i)   
        b.bind("<Button-1>",buttonCallBack)   
    b=Button(root,text="=")   
    b.grid(row=6,columnspan=2,sticky="we")   
    b.bind("<Button-1>",buttonCallBack)   
    root.mainloop()  

来自：http://blog.csdn.net/ccy0815ccy/article/details/42426373