PROGRAMMING
Php
Delimiters
Any character can be used as a delimiter. Every metacharacter represents a single character in the matched expression.
echo preg_match("/[a-z]/", "abcde"); // common delimiter
echo preg_match("&[a-z&]&", "abcde"); // escaped delimiter
echo preg_match("/./", "abc"); // true
// match any character
echo preg_match("/^bc/", "abc"); // false
// match start of the string, then match b, match c
echo preg_match("/c$/", "abc"); // 1
// c, end of the string
Multiple
You can perform multiple matches on a given string using preg_match_all()
$matches = array();
if (preg_match_all("/([abc])\d/", "a1bb b2cc c3dd", $matches)) {
var_dump($matches);
// [0] => a1, b2, c3
// [1] => a, b, c
}
Replace
! You can replace text that matches a pattern. It is even possible to reuse captured subpatterns directly in the substitution string.
echo preg_replace("/a/", "x", "abc"); // xbc
echo preg_replace("/a{2}/", "x", "abaac"); // abxc
$str = "XabcX";
$pattern = "/X(.*)X/";
preg_match($pattern, $str, $matches);
var_dump($matches); //[1] => "abc"
$replace = preg_replace($pattern, "Y $1 Y", $str);
echo $replace; // Y abc Y
$array = array("[b]abc[/b]", "[i]abc[/i]");
$result = preg_replace(
<span class='keyword_code'>array</span>(
"|[b](.*)[/b]|",
"|[i](.*)[/i]|",
),
array(
"<b>$1</b>",
"<i>$1</i>",
),
$array
);
print_r($array); // [0] => [b]abc[/b] [1] => [i]abc[/i]
print_r($result); // [0] => <b>abc</b> [1] => <i>abc</i>
➥ Questions
