#!/usr/bin/env python3 """ 简单但功能齐全的桌面计算器（Tkinter） 保存为 calc_gui.py 后运行: python calc_gui.py """ import tkinter as tk from tkinter import ttk, messagebox from tkinter.scrolledtext import ScrolledText import ast import math # ---------- 安全求值（仅允许数学表达式） ---------- _SAFE_NAMES = { # 常用数学函数 'sin': math.sin, 'cos': math.cos, 'tan': math.tan, 'asin': math.asin, 'acos': math.acos, 'atan': math.atan, 'sinh': math.sinh, 'cosh': math.cosh, 'tanh': math.tanh, 'exp': math.exp, 'log': math.log, 'log10': math.log10, 'sqrt': math.sqrt, 'pow': pow, 'abs': abs, 'round': round, # 常数 'pi': math.pi, 'e': math.e } _ALLOWED_NODES = ( ast.Expression, ast.BinOp, ast.UnaryOp, ast.Num, ast.Constant, ast.Call, ast.Name, ast.Load, ast.Add, ast.Sub, ast.Mult, ast.Div, ast.Pow, ast.Mod, ast.FloorDiv, ast.UAdd, ast.USub, ast.Tuple, ast.List ) def safe_eval(expr: str): """ 使用 AST 安全解析并计算表达式。 支持 ^ 作为幂运算（会在前端被替换成 **）。 """ if not expr: raise ValueError("空表达式") # 替换常见符号 expr = expr.replace('^', '**') try: node = ast.parse(expr, mode='eval') except Exception as e: raise ValueError(f"解析错误: {e}") for n in ast.walk(node): if not isinstance(n, _ALLOWED_NODES): raise ValueError(f"不允许的表达式或节点: {type(n).__name__}") if isinstance(n, ast.Call): if not (isinstance(n.func, ast.Name) and n.func.id in _SAFE_NAMES): raise ValueError(f"调用未允许的函数: {ast.dump(n)}") if isinstance(n, ast.Name): if n.id not in _SAFE_NAMES: raise ValueError(f"未允许的名称: {n.id}") compiled = compile(node, "", "eval") return eval(compiled, {"__builtins__": {}}, _SAFE_NAMES) # ---------- GUI 应用 ---------- class Calculator(tk.Tk): def __init__(self): super().__init__() self.title("Python 计算器") self.resizable(False, False) self._make_widgets() self.memory = 0.0 self.history = [] def _make_widgets(self): frm = ttk.Frame(self, padding=8) frm.grid(row=0, column=0) # 显示文本 self.entry_var = tk.StringVar() entry = ttk.Entry(frm, textvariable=self.entry_var, font=( "Consolas", 18), justify='right', width=22) entry.grid(row=0, column=0, columnspan=6, pady=(0, 8)) entry.focus_set() # 历史显示（滚动） self.history_box = ScrolledText( frm, width=34, height=8, state='disabled', font=("Consolas", 10)) self.history_box.grid(row=1, column=0, columnspan=6, pady=(0, 8)) # 按钮布局 buttons = [ ('MC', self.mem_clear), ('MR', self.mem_recall), ('M+', self.mem_add), ('M-', self.mem_sub), ('←', self.backspace), ('C', self.clear), ('7', lambda: self.insert('7')), ('8', lambda: self.insert('8')), ('9', lambda: self.insert( '9')), ('/', lambda: self.insert('/')), ('sqrt', lambda: self.insert('sqrt(')), ('^', lambda: self.insert('^')), ('4', lambda: self.insert('4')), ('5', lambda: self.insert('5')), ('6', lambda: self.insert( '6')), ('*', lambda: self.insert('*')), ('x^2', self.square), ('1/x', self.reciprocal), ('1', lambda: self.insert('1')), ('2', lambda: self.insert('2')), ('3', lambda: self.insert( '3')), ('-', lambda: self.insert('-')), ('(', lambda: self.insert('(')), (')', lambda: self.insert(')')), ('0', lambda: self.insert('0')), ('.', lambda: self.insert('.')), ('±', self.negate), ('+', lambda: self.insert('+')), ('%', self.percent), ('=', self.calculate), ] r = 2 c = 0 for (text, cmd) in buttons: b = ttk.Button(frm, text=text, width=6, command=cmd) b.grid(row=r, column=c, padx=2, pady=2) c += 1 if c > 5: c = 0 r += 1 # 额外科学函数按钮行 funcs = [('sin', 'sin('), ('cos', 'cos('), ('tan', 'tan('), ('log', 'log('), ('ln', 'log('), ('pi', 'pi')] r += 1 c = 0 for label, to_ins in funcs: b = ttk.Button(frm, text=label, width=6, command=lambda s=to_ins: self.insert(s)) b.grid(row=r, column=c, padx=2, pady=4) c += 1 # 绑定键盘 self.bind_all('', lambda e: self.calculate()) self.bind_all('', lambda e: self.calculate()) self.bind_all('', lambda e: self.backspace()) self.bind_all('', lambda e: self.clear()) for k in '0123456789.+-*/()%^': self.bind_all(k, lambda e, ch=k: self.insert(ch)) # 功能实现 def insert(self, s): cur = self.entry_var.get() self.entry_var.set(cur + s) def clear(self): self.entry_var.set('') def backspace(self): cur = self.entry_var.get() if cur: self.entry_var.set(cur[:-1]) def negate(self): cur = self.entry_var.get().strip() if not cur: return try: # 尝试计算当前表达式值并取相反数（安全） val = safe_eval(cur) self.entry_var.set(str(-val)) except Exception: # 若无法直接计算（表达式不完整），则尝试在前面插入负号 if cur.startswith('-'): self.entry_var.set(cur[1:]) else: self.entry_var.set('-' + cur) def percent(self): cur = self.entry_var.get().strip() if not cur: return try: val = safe_eval(cur) self.entry_var.set(str(val / 100.0)) except Exception as e: messagebox.showerror("错误", f"无法计算百分比: {e}") def square(self): cur = self.entry_var.get().strip() if not cur: return try: val = safe_eval(cur) self.entry_var.set(str(val * val)) except Exception as e: messagebox.showerror("错误", f"无法平方: {e}") def reciprocal(self): cur = self.entry_var.get().strip() if not cur: return try: val = safe_eval(cur) if val == 0: raise ZeroDivisionError("除以零") self.entry_var.set(str(1.0 / val)) except Exception as e: messagebox.showerror("错误", f"无法求倒数: {e}") def calculate(self): expr = self.entry_var.get().strip() if not expr: return try: result = safe_eval(expr) # 显示结果并记录历史 self.entry_var.set(str(result)) self._add_history(expr, result) except Exception as e: messagebox.showerror("计算错误", str(e)) def _add_history(self, expr, result): self.history.append((expr, result)) self.history_box.config(state='normal') self.history_box.insert('end', f"{expr} = {result}\n") self.history_box.see('end') self.history_box.config(state='disabled') # 内存功能 def mem_clear(self): self.memory = 0.0 messagebox.showinfo("内存", "已清除内存") def mem_recall(self): self.entry_var.set(str(self.memory)) def mem_add(self): cur = self.entry_var.get().strip() if not cur: return try: val = safe_eval(cur) self.memory += val messagebox.showinfo("内存", f"内存已更新：{self.memory}") except Exception as e: messagebox.showerror("错误", f"无法加入内存: {e}") def mem_sub(self): cur = self.entry_var.get().strip() if not cur: return try: val = safe_eval(cur) self.memory -= val messagebox.showinfo("内存", f"内存已更新：{self.memory}") except Exception as e: messagebox.showerror("错误", f"无法从内存减去: {e}") if __name__ == "__main__": app = Calculator() app.mainloop()