<b>example: </b>, example:
<div align="left">this is a test</div>, this is a test
In this case, $matches is the first set of matches, and
$matches has text matched by full pattern, $matches
has text matched by first subpattern and so on. Similarly,
$matches is the second set of matches, etc.
If this flag is passed, for every occurring match the appendant string
offset will also be returned. Note that this changes the return
value in an array where every element is an array consisting of the
matched string at offset 0 and its string offset
into subject at offset 1.
This flag is available since PHP 4.3.0 .
If no order flag is given, PREG_PATTERN_ORDER is
Normally, the search starts from the beginning of the subject string. The
optional parameter offset can be used to specify
the alternate place from which to start the search.
The offset parameter is available since
Using offset is not equivalent to
passing substr($subject, $offset) to
preg_match_all() in place of the subject string, because
pattern can contain assertions such as
^, $ or
(?<=x). See preg_match() for
Returns the number of full pattern matches (which might be zero),
or FALSE if an error occurred.
Example 1. Getting all phone numbers out of some text.
<?php // The \\2 is an example of backreferencing. This tells pcre that // it must match the second set of parentheses in the regular expression // itself, which would be the ([\w]+) in this case. The extra backslash is // required because the string is in double quotes. $html = "<b>bold text</b><a href=howdy.html>click me</a>";