From 71abbbf95e88e66a4256a4390fea816f10585c27 Mon Sep 17 00:00:00 2001
From: sjtu-cz <1124963678@qq.com>
Date: Mon, 13 Mar 2017 21:25:25 +0800
Subject: [PATCH] Create calc.py

---
 calc.py | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 52 insertions(+)
 create mode 100644 calc.py

diff --git a/calc.py b/calc.py
new file mode 100644
index 0000000..267a42d
--- /dev/null
+++ b/calc.py
@@ -0,0 +1,52 @@
+# coding=utf-8
+from Tkinter import *
+
+def userinput(text):    #按键返回函数
+    content = display.get() + text
+    display.set(content)
+
+def clear():   #清空函数
+    display.set('')
+
+def dell():     #删除一字符函数
+    display.set(str(display.get()[:-1]))
+
+def calculate():   #调用eval计算表达式
+    try:
+        num=display.get()
+        res=eval(num)
+        display.set(num+'='+str(res))
+    except:
+        display.set('error!')
+
+def main():
+    root = Tk()
+    root.title('计算器-yh')
+    global display
+    display = StringVar()
+    root.geometry('275x215+200+200')
+    root.resizable(0,0)
+    label = Label(root,relief='sunken',borderwidth=3, anchor=SE)#显示窗口
+    label['textvariable'] = display
+    label.config(bg='white', width=38, height=2)
+    label.grid(row=0, column=0, columnspan=4,pady=10)
+    positions=[(x,y) for x in range(1,6) for y in range(4)]
+    tests=['Cls','Bck','(',')',
+           '7','8','9','/',
+           '4','5','6','*',
+           '1','2','3','-',
+           '0','.','=','+']
+    for i in zip(tests,positions): #将两个列表并列
+        text=i[0]
+        row=i[1][0]
+        column=i[1][1]
+        if text=='Cls':
+            Button(root, text=text, width=8, command=lambda text=text: clear()).grid(row=row, column=column)
+        elif text=='Bck':
+            Button(root, text=text, width=8, command=lambda text=text: dell()).grid(row=row, column=column)
+        elif text=='=':
+            Button(root, text=text, bg='green', width=8, command=lambda text=text: calculate()).grid(row=row, column=column)
+        else:
+            Button(root, text=text, width=8, command=lambda text=text: userinput(text)).grid(row=row, column=column)
+    root.mainloop()
+main()