问题
I am currently matching HTML using this code:
preg_match('/<\/?([a-z]+)[^>]*>|&#?[a-zA-Z0-9]+;/u', $html, $match, PREG_OFFSET_CAPTURE, $position)
It matches everything perfect, however if I have a multibyte character, it counts it as 2 characters when giving back the position.
For example the returned $match
array would give something like:
array
0 =>
array
0 => string '<br />' (length=6)
1 => int 132
1 =>
array
0 => string 'br' (length=2)
1 => int 133
The real number for the <br />
match is 128, but there are 4 multibyte characters, so it's giving 132. I really thought adding the /u modifier would make it realize what's going on, but no luck there.
回答1:
I looked at this suggestion from @Qtax:
UTF-8 characters in preg_match_all (PHP)
And for some more reference, this bug surfaced while using this: Truncate text containing HTML, ignoring tags
The gist of the change is this:
$orig_utf = 'UTF-8';
$new_utf = 'UTF-32';
mb_regex_encoding( $new_utf );
$html = mb_convert_encoding( $html, $new_utf, $orig_utf );
$end_char = mb_convert_encoding( $end_char, $new_utf, $orig_utf );
mb_ereg_search_init( $html );
$pattern = '</?([a-z]+)[^>]*>|&#?[a-zA-Z0-9]+;';
$pattern = mb_convert_encoding( $pattern, $new_utf, $orig_utf );
while ( $printed < $limit && $tag_match = mb_ereg_search_pos( $pattern, $html ) ) {
$tag_position = $tag_match[0]/4;
$tag_length = $tag_match[1];
$tag = mb_substr( $html, $tag_position, $tag_length/4, $new_utf );
$tag_name = preg_replace( '/[\s<>\/]+/', '', $tag );
// Print text leading up to the tag.
$str = mb_substr($html, $position, $tag_position - $position, $new_utf );
.......
}
Also in reference to the truncate HTML page, there are other neccessary changes:
$first_char = mb_substr( $tag, 0, 1, $new_utf );
if ( $first_char == mb_convert_encoding( '&', $new_utf ) ) {
...
}
My text editor is UTF-8 so if I was comparing the 32 to my file's ampersand, it wouldn't work.
回答2:
If you need quick fix and don't care about speed:
$mb_pos = mb_strlen( substr($string, 0, $pos) );
回答3:
Have you looked into http://www.php.net/manual/en/function.mb-ereg.php ?
来源:https://stackoverflow.com/questions/9950842/how-to-get-correct-list-position-in-multi-byte-string-using-preg-match