test_preg_match_all

<?php

//\\2是一个后向引用的示例. 这会告诉pcre它必须匹配正则表达式中第二个圆括号(这里是([\w]+))
//匹配到的结果. 这里使用两个反斜线是因为这里使用了双引号.
$html = "<
b>
bold text<
/b>
<img href=howdy.html>
click me<
/a>";

preg_match_all("/(<
([\w]+)[^>
]*>
)(.*?)(<
\/\\2>
)/", $html, $matches, PREG_SET_ORDER);

foreach ($matches as $val) {
    echo "matched: " . $val[0] . "\n";

    echo "part 1: " . $val[1] . "\n";

    echo "part 2: " . $val[2] . "\n";

    echo "part 3: " . $val[3] . "\n";

    echo "part 4: " . $val[4] . "\n\n";

}
?>