python3全角与半角字符转换

一、背景介绍

  • 解决什么问题:快速方便的对文本进行全角半角自动转换
  • 适用什么场景:学生答题数据中全角字符替换为半角字符

二、全角半角原理

  • 全角即:Double Byte Character,简称DBC
  • 半角即:Single Byte Character,简称SBC
  • 在 windows 中,中文和全角字符都占两个字节,并且使用了 ascii chart 2 (codes 128–255);
  • 全角字符的第一个字节总是被置为 163,而第二个字节则是相同半角字符码加上128(不包括空格,全角空格和半角空格也要考虑进去);
  • 对于中文来说,它的第一个字节被置为大于163,如’阿’为:176 162,检测到中文时不进行转换。
  • 例如:半角 a 为 65,则全角 a 是 163(第一个字节)、193(第二个字节,128+65)。

全角半角示例:(文本 test.txt 包含全角和半角字符)

F:\test>type test.txt
123456
123456
abcdefg
abcdefg
中国你好

三、使用 Python3 实现全角半角转换


# -*- coding:utf-8 -*-
# i@mail.chenpeng.info

”’
全角即:Double Byte Character,简称:DBC
半角即:Single Byte Character,简称:SBC
”’

def DBC2SBC(ustring):
     ”’ 全角转半角 ”’
     rstring = “”
     for uchar in ustring:
         inside_code = ord(uchar)
         if inside_code == 0x3000:
             inside_code = 0x0020
         else:
             inside_code -= 0xfee0
             if not (0x0021 <= inside_code and inside_code <= 0x7e):
                 rstring += uchar
                 continue
         rstring += chr(inside_code)
     return rstring

def SBC2DBC(ustring):
     ”’ 半角转全角 ”’
     rstring = “”
     for uchar in ustring:
         inside_code = ord(uchar)
         if inside_code == 0x0020:
             inside_code = 0x3000
         else:
             if not (0x0021 <= inside_code and inside_code <= 0x7e):
                 rstring += uchar
                 continue
             inside_code += 0xfee0
         rstring += chr(inside_code)
     return rstring

s = ”’
array(‘0’ => ‘0’, ‘1’ => ‘1’, ‘2’ => ‘2’, ‘3’ => ‘3’, ‘4’ => ‘4’,
         ‘5’ => ‘5’, ‘6’ => ‘6’, ‘7’ => ‘7’, ‘8’ => ‘8’, ‘9’ => ‘9’,
         ‘A’ => ‘A’, ‘B’ => ‘B’, ‘C’ => ‘C’, ‘D’ => ‘D’, ‘E’ => ‘E’,
         ‘F’ => ‘F’, ‘G’ => ‘G’, ‘H’ => ‘H’, ‘I’ => ‘I’, ‘J’ => ‘J’,
         ‘K’ => ‘K’, ‘L’ => ‘L’, ‘M’ => ‘M’, ‘N’ => ‘N’, ‘O’ => ‘O’,
         ‘P’ => ‘P’, ‘Q’ => ‘Q’, ‘R’ => ‘R’, ‘S’ => ‘S’, ‘T’ => ‘T’,
         ‘U’ => ‘U’, ‘V’ => ‘V’, ‘W’ => ‘W’, ‘X’ => ‘X’, ‘Y’ => ‘Y’,
         ‘Z’ => ‘Z’, ‘a’ => ‘a’, ‘b’ => ‘b’, ‘c’ => ‘c’, ‘d’ => ‘d’,
         ‘e’ => ‘e’, ‘f’ => ‘f’, ‘g’ => ‘g’, ‘h’ => ‘h’, ‘i’ => ‘i’,
         ‘j’ => ‘j’, ‘k’ => ‘k’, ‘l’ => ‘l’, ‘m’ => ‘m’, ‘n’ => ‘n’,
         ‘o’ => ‘o’, ‘p’ => ‘p’, ‘q’ => ‘q’, ‘r’ => ‘r’, ‘s’ => ‘s’,
         ‘t’ => ‘t’, ‘u’ => ‘u’, ‘v’ => ‘v’, ‘w’ => ‘w’, ‘x’ => ‘x’,
         ‘y’ => ‘y’, ‘z’ => ‘z’,
         ‘(’ => ‘(‘, ‘)’ => ‘)’, ‘〔’ => ‘[‘, ‘〕’ => ‘]’, ‘【’ => ‘[‘,
         ‘】’ => ‘]’, ‘〖’ => ‘[‘, ‘〗’ => ‘]’, ‘”‘ => ‘[‘, ‘”‘ => ‘]’,
         ‘\” => ‘[‘, ‘\” => ‘]’, ‘{’ => ‘{‘, ‘}’ => ‘}’, ‘《’ => ‘<‘,
         ‘》’ => ‘>’,
         ‘%’ => ‘%’, ‘+’ => ‘+’, ‘—’ => ‘-‘, ‘-’ => ‘-‘, ‘~’ => ‘-‘,
         ‘:’ => ‘:’, ‘。’ => ‘.’, ‘、’ => ‘,’, ‘,’ => ‘.’, ‘、’ => ‘.’,
         ‘;’ => ‘,’, ‘?’ => ‘?’, ‘!’ => ‘!’, ‘…’ => ‘-‘, ‘‖’ => ‘|’,
         ‘”‘ => ‘”‘, ‘\” => ‘`’, ‘\” => ‘`’, ‘|’ => ‘|’, ‘〃’ => ‘”‘,
         ‘ ’ => ‘ ‘);
         ”’

# 全角转半角
print(DBC2SBC(s))

# 半角转全角
print(SBC2DBC(s))

s = ”’中文测试”’

# 全角转半角
print(DBC2SBC(s))

# 半角转全角
print(SBC2DBC(s))


四、参考资料

http://thinkerou.com/2015-06/covert-dbc-sbc/

About 智足者富

http://chenpeng.info

发表评论

电子邮件地址不会被公开。 必填项已用*标注

You may use these HTML tags and attributes:

<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>