PCRE 函数
As I had to work with PHP5.2.X and needed preg_filter I wrote a quick and dirty workaround.
<?php
if (!function_exists('preg_filter')) {
function preg_filter($pattern, $replace, $subject, $limit = -1 , &$count = null) {
if(!is_array($subject)) {
$noArray = 1 ;
$subject = array($subject);
}
$preg = preg_replace($pattern, $replace, $subject, $limit, &$count);
$diff = array_diff($preg, $subject);
if($noArray == 1) $diff = implode($diff) ;
return $diff ;
}
}
?>
preg_filter
(PHP 5 >= 5.3.0)
preg_filter — 执行一个正则表达式搜索和替换
说明
mixed preg_filter
( mixed
$pattern
, mixed $replacement
, mixed $subject
[, int $limit = -1
[, int &$count
]] )preg_filter()等价于preg_replace() 除了它仅仅返回(可能经过转化)与目标匹配的结果. 这个函数怎样工作的更详细信息请阅读 preg_replace()文档.
返回值
如果subject是一个数组, 返回一个数组,
其他情况返回一个字符串.
如果没有找到匹配或者发生了错误, 当subject是数组
时返回一个空数组, 其他情况返回NULL.
范例
Example #1 比较preg_filter() 和preg_replace()的示例
<?php
$subject = array('1', 'a', '2', 'b', '3', 'A', 'B', '4');
$pattern = array('/\d/', '/[a-z]/', '/[1a]/');
$replace = array('A:$0', 'B:$0', 'C:$0');
echo "preg_filter returns\n";
print_r(preg_filter($pattern, $replace, $subject));
echo "preg_replace returns\n";
print_r(preg_replace($pattern, $replace, $subject));
?>
以上例程会输出：
preg_filter returns
Array
(
[0] => A:C:1
[1] => B:C:a
[2] => A:2
[3] => B:b
[4] => A:3
[7] => A:4
)
preg_replace returns
Array
(
[0] => A:C:1
[1] => B:C:a
[2] => A:2
[3] => B:b
[4] => A:3
[5] => A
[6] => B
[7] => A:4
)
参见
- PCRE Patterns
- preg_replace() - 执行一个正则表达式的搜索和替换
- preg_replace_callback() - 执行一个正则表达式搜索并且使用一个回调进行替换
- preg_grep() - 返回匹配模式的数组条目
- preg_last_error() - 返回最后一个PCRE正则执行产生的错误代码
add a note
User Contributed Notes
preg_filter
sajina_99 at hotmail dot de
25-Sep-2011 07:07
MrBertie
31-Dec-2010 02:35
Another way to filter an array, and simply return the matching items: preg_grep!
Eric Naeseth
17-Dec-2010 06:38
If you want to just filter an array based on a regular expression, without replacing any of the array values, try RegexIterator: http://us3.php.net/manual/en/class.regexiterator.php