» Relativen / absoluten Link in Deeplink umwandeln

<img src="./images/image1.jpg" />
<img src="images/image2.jpg" />
<img src="/images/image3.jpg" />

function deeplink($base_url, $resource) {
	// remove fragment
	if (($anchor_pos = strpos($resource, '#')) !== false) {
		$resource = substr($resource, 0, $anchor_pos);
	}
	if (!$resource) {
		return $base_url;
	}
	// nothing to do as $ressource contains scheme (http://, mailto:, javascript:, etc.)
	if (preg_match('~^[0-9a-z.\-+]{2,}:~i', $resource)) {
		return resolvepath($resource);
	}
	// base url must contain a scheme! http://en.wikipedia.org/wiki/URI_scheme#Generic_syntax
	if (!preg_match('~^[0-9a-z.\-+]{2,}://~i', $base_url, $m)) {
		return false;
	}
	// obtain the first slash after scheme (we assume the url includes this)
	$first_slash_pos = strpos($base_url, '/', strpos($base_url, '//') + 2);
	$root_url = substr($base_url, 0, $first_slash_pos + 1);
	// protocol independent "//www.example.org" works for "https://" and "http://" http://stackoverflow.com/a/2216721/318765
	if (isset($resource[1]) && $resource[0] == '/' && $resource[1] == '/') {
		$deeplink = $m[0] . substr($resource, 2);
	}
	// absolute link
	else if ($resource[0] == '/') {
		$deeplink = $root_url . substr($resource, 1);
	}
	// relative link
	else {
		if (isset($resource[1]) && $resource[0] == '.' && $resource[1] == '/') {
			$resource = substr($resource, 2);
		}
		$deeplink = $base_url . $resource;
	}
	return resolvepath($deeplink);
}

• base URL endent auf ein Slash also z.B. http://example.com/foo/
• eine Ressource wie unser ./images/image1.jpg

$img_src = deeplink('http://example.com/foo/', "/images/image3.jpg");

http://example.com/images/image3.jpg

Mach mit!