【原創】python 比較兩個版本號大小

# -*- coding: utf-8 -*-
__author__ = 'ypp'

import re

def versionCompare(v1="1.1.1", v2="1.2"):
    v1_check = re.match("\d+(\.\d+){0,2}", v1)
    v2_check = re.match("\d+(\.\d+){0,2}", v2)
    if v1_check is None or v2_check is None or v1_check.group() != v1 or v2_check.group() != v2:
        return "版本號格式不對，正確的應該是x.x.x,只能有3段"
    v1_list = v1.split(".")
    v2_list = v2.split(".")
    v1_len = len(v1_list)
    v2_len = len(v2_list)
    if v1_len > v2_len:
        for i in range(v1_len - v2_len):
            v2_list.append("0")
    elif v2_len > v1_len:
        for i in range(v2_len - v1_len):
            v1_list.append("0")
    else:
        pass
    for i in range(len(v1_list)):
        if int(v1_list[i]) > int(v2_list[i]):
            return "v1大"
        if int(v1_list[i]) < int(v2_list[i]):
            return "v2大"
    return "相等"

# 測試用例
print(versionCompare(v1="", v2="")) 
print(versionCompare(v1="1.0.a", v2="d.0.1"))
print(versionCompare(v1="1.0.1", v2="1.0.1"))
print(versionCompare(v1="1.0.2", v2="1.0.1"))
print(versionCompare(v1="1.0.1", v2="1.0.2"))
print(versionCompare(v1="1.0.11", v2="1.0.2"))

設計思想： 
1.使用正則表達式判斷版本號格式是否正確 
2.將字元串用”.”分隔成數組 
3.比較數組長度，將長度短的數組用“0”補齊成相等長度數組 
4.逐個遍曆數組元素，比較大小

測試用例： 
1.版本號為空 
2.版本號含非數字 
3.版本號長度不一致 
4.版本號以點為分隔，逐位比較