Python使用Tkinter实现一个罗马数字转整数的简单工具

def to_int(roman):
    mapping = {
        "I": 1,
        "V": 5,
        "X": 10,
        "L": 50,
        "C": 100,
        "D": 500,
        "M": 1000
    }
    result = 0
    prev_value = 0
    for char in roman:
        curr_value = mapping[char]
        result += curr_value
        if prev_value != 0 and prev_value < curr_value:
            result -= prev_value * 2
        prev_value = curr_value
    return result

from tkinter import *
from tkinter import ttk
import re

def convert():
    try:
        raw = roman.get().strip()
        if raw == "":
            result.set("无效输入")
            return
        if re.match("^(M{0,3})(C{0,3}|CD|DC{0,3}|CM)(X{0,3}|XL|LX{0,3}|XC)(I{0,3}|IV|VI{0,3}|IX)$", raw):
            result.set(to_int(raw))
        else:
            result.set("无效输入")
            return
    except ValueError:
        pass

def to_int(roman):
    mapping = {
        "I": 1,
        "V": 5,
        "X": 10,
        "L": 50,
        "C": 100,
        "D": 500,
        "M": 1000
    }
    result = 0
    prev_value = 0
    for char in roman:
        curr_value = mapping[char]
        result += curr_value
        if prev_value != 0 and prev_value < curr_value:
            result -= prev_value * 2
        prev_value = curr_value
    return result


root = Tk()
root.title("罗马数字转整数小工具")

mainframe = ttk.Frame(root, padding=(3, 3, 12, 12))
mainframe.grid(column=0, row=0, sticky=(N, W, E, S))

roman = StringVar()
roman_entry = ttk.Entry(mainframe, width=12, textvariable=roman)
roman_entry.grid(column=2, row=1, sticky=(W, E))

ttk.Button(mainframe, text="转化为整数", command=convert).grid(column=1, row=2, sticky=W)

ttk.Label(mainframe, text="请输入一个罗马数字").grid(column=1, row=1, sticky=W)

result = StringVar()
ttk.Label(mainframe, textvariable=result).grid(column=2, row=2, sticky=W)

root.columnconfigure(0, weight=1)
root.rowconfigure(0, weight=1)
mainframe.columnconfigure(2, weight=1)
for child in mainframe.winfo_children(): 
    child.grid_configure(padx=5, pady=5)

roman_entry.focus()
root.bind("<Return>", convert)

root.mainloop()

python3 from_roman.py