Python稳基修炼的经典案例13（计算机二级、初学者必会的字符文件处理）

快来打我* 2022-12-06 01:24 98阅读 0赞

### 文章目录 ###

*   *   *   *  1、统计基础中文字符
             *  2、中文版凯撒加密
             *  3、提取网页链接，即“href=”后面的的链接

#### 1、统计基础中文字符 ####

*  题：给定基础中文字符的unicode编码范围为｛0x4e00, 0x9fa5｝，统计文本文件中存在多少的基础中文字符及其对应的次数

fi = open("a.txt", 'r', encoding='gbk')
    fo = open("c.txt", 'w', encoding='gbk')
    txt = fi.read()
    d = { }
    for c in txt:
        if 0x4e00 <= ord(c) <= 0x9fa5:
            d[c] = d.get(c, 0) + 1
            ls = []
    for key in d:
        ls.append("{}(0x{:x}):{}".format(key, ord(key), d[key]))
    fo.write("，".join(ls))
    fi.close()
    fo.close()

![01][]

--------------------

#### 2、中文版凯撒加密 ####

s = input("请输入明文：")
    d = { }
    for c in [0x4e00, 0x9fa5]:
        for i in range(20902):
            d[chr(i+c)] = chr((i+10451)%20902+c)
    print("凯撒加密后的文字：" + " ".join([d.get(c, c) for c in s]))

![02][]

--------------------

#### 3、提取网页链接，即“href=”后面的的链接 ####

fi = open("sweb.html", 'r', encoding='utf-8')
    fo = open("text-urls.txt", 'w', encoding='utf-8')
    txt = fi.read()
    ls = txt.split(" ")
    urls = []
    for item in ls:
        if item[:5] == "href=" and item[6:13] == "http://":
            urls.append(item[6:-1])
            for item in urls:
                fo.write(item+'\n')
    fi.close()
    fo.close()

[01]: /images/20221123/9fbb70c69f2a4380826664b7d67bf639.png
[02]: /images/20221123/ddfa0e751d2c4c47aab9d078b474bdc7.png