shortcodeparse.php

<?php
//The content which should be parsed
$content = '<p>Hello, my name is John an my age is [calc-age day="4" month="10" year="1991"].</p>';
$content .= '<p>Hello, my name is Carol an my age is [calc-age day="26" month="11" year="1996"].</p>';

//The array with all the shortcode handlers. This is just a regular associative array with anonymous functions as values. A very cool new feature in PHP, just like callbacks in JavaScript or delegates in C#.
$shortcodes = array(
	"calc-age" => function($data){
		$content = "";
		//Calculate the age
		if(isset($data["day"], $data["month"], $data["year"])){
			$age = date("Y") - $data["year"];
			if(date("m") < $data["month"]){
				$age--;
			}
			if(date("m") == $data["month"] && date("d") < $data["day"]){
				$age--;
			}
			$content = $age;
		}
		return $content;
	}
);
//http://stackoverflow.com/questions/18196159/regex-extract-variables-from-shortcode
function handleShortcodes($content, $shortcodes){
	//Loop through all shortcodes
	foreach($shortcodes as $key => $function){
		$dat = array();
		preg_match_all("/\[".$key." (.+?)\]/", $content, $dat);
		if(count($dat) > 0 && $dat[0] != array() && isset($dat[1])){
			$i = 0;
			$actual_string = $dat[0];
			foreach($dat[1] as $temp){
				$temp = explode(" ", $temp);
				$params = array();
				foreach ($temp as $d){
					list($opt, $val) = explode("=", $d);
					$params[$opt] = trim($val, '"');
				}
				$content = str_replace($actual_string[$i], $function($params), $content);
				$i++;
			}
		}
	}
	return $content;
}
echo handleShortcodes($content, $shortcodes);
?>