I'm trying to strip all characters from a string except:
$)_)U+0080 and U+FFFFI've got the first three conditions by doing this:
preg_replace('/[^a-zA-Zd$_]+/', '', $foo);
How do I go about matching the fourth condition? I looked at using X but there has to be a better way than listing out 65000+ characters.
I finally found working solution thanks to this Tibor's answer here: Regex to ignore accents? PHP
My function highlights text ignoring diacritics, spaces, apostrophes and dashes:
function highlight($pattern, $string)
{
$array = str_split($pattern);
//add or remove characters to be ignored
$pattern=implode('[s'-]*', $array);
//list of letters with diacritics
$replacements = Array("a" => "[áa]", "e"=>"[ée]", "i"=>"[íi]", "o"=>"[óo]", "u"=>"[úu]", "A" => "[ÁA]", "E"=>"[ÉE]", "I"=>"[ÍI]", "O"=>"[ÓO]", "U"=>"[ÚU]");
$pattern=str_replace(array_keys($replacements), $replacements, $pattern);
//instead of <u> you can use <b>, <i> or even <div> or <span> with css class
return preg_replace("/(" . $pattern . ")/ui", "<u>\1</u>", $string);
}
The syntax of your unicode range will not do what you expect.
The raw r'' string prevents u escapes from being parsed, and the regex engine will not do this. The only range in this set is [0-]:
>>> re.compile(r'[u0020-u00d7ff]', re.DEBUG)
in
literal 117
literal 48
literal 48
literal 50
range (48, 117)
literal 48
literal 48
literal 100
literal 55
literal 102
literal 102
Making it a Unicode literal causes u parsing while leaving other backslashes alone (although that’s not a concern here), but the leading zeroes are messing it up. The syntax is uxxxx or Uxxxxxxxx, so it’s parsed as "u00d7, f, f".
>>> re.compile(ur'[u0020-u00d7ff]', re.DEBUG)
in
range (32, 215)
literal 102
literal 102
Removing the leading zeroes or switching to U0000d7ff will fix it:
>>> re.compile(ur'[u0020-ud7ff]', re.DEBUG)
in
range (32, 55295)
Regex is not able to change characters by itself, it can only change their order and/or add additional characters/delete some of them.
There is preg_replace_callback or /e flag, but they can manipulate only with known functions, and therefore can't do better than strtolower.
If you can't rely on existense of mb_strolower function, you will have to implement it yourself.
You can use:
w- is equivalent of[a-zA-Z0-9_]x{0080}-x{FFFF}to match characters between code pointsU+0080andU+FFFF`/ufor unicode support in regex