Funzione molto utile per formattare il testo XML in uscita (ad esempio da DomDocument).
function formatXmlString($xml, $indentBase = 0, $indentString = ' ') { // add marker linefeeds to aid the pretty-tokeniser (adds a linefeed between all tag-end boundaries) $xml = preg_replace('/(>)(<)(\/*)/', "$1\n$2$3", $xml); // now indent the tags $token = strtok($xml, "\n"); $result = ''; // holds formatted version as it is built $pad = ($indentBase > 0) ? $indentBase : 0; // initial indent $matches = array(); // returns from preg_matches() // scan each line and adjust indent based on opening/closing tags while ($token !== false): // test for the various tag states // 1. open and closing tags on same line - no change if (preg_match('/.+<\/\w[^>]*>$/', $token, $matches)): $indent = 0; // 2. closing tag - outdent now elseif (preg_match('/^<\/\w/', $token, $matches)): $pad--; // 3. opening tag - don't pad this one, only subsequent tags elseif (preg_match('/^<\w[^>]*[^\/]>.*$/', $token, $matches)): $indent = 1; // 4. no indentation needed else: $indent = 0; endif; // pad the line with the required number of leading spaces $line = str_pad($token, strlen($token) + $pad, $indentString, STR_PAD_LEFT); $result .= $line . "\n"; // add to the cumulative result, with linefeed $token = strtok("\n"); // get the next token $pad += $indent; // update the pad size for subsequent lines endwhile; return $result; }
Tratta (e modificata) da recurser.com.
http://recurser.com/articles/2007/04/05/format-xml-with-php/