[Resolved] XML parsing - v. simple question

[Norman_Graham]

Hi all

I feel a bit stupid asking this question, because it's definitely beginner's stuff, but I've never come across it before and don't know where to find the answers in the manual (I have tried searching the manual and this forum, but don't have enough to go on). Here's the code I'm working with:

class RSSParser { 

   var $insideitem = false; 
   var $tag = ""; 
   var $title = ""; 
   var $description = ""; 
   var $link = ""; 

   function startElement($parser, $tagName, $attrs) { 
       if ($this->insideitem) { 
           $this->tag = $tagName; 
       } elseif ($tagName == "ITEM") { 
           $this->insideitem = true; 
       } 
   } 

   function endElement($parser, $tagName) { 
       if ($tagName == "ITEM") { 
           printf("<p><b><a href=\"%s\" target=\"_blank\">%s</a></b></p>", 
             trim($this->link),htmlspecialchars(trim($this->title))); 
           printf("<p>%s</p>", 
             htmlspecialchars(trim($this->description))); 
           $this->title = ""; 
           $this->description = ""; 
           $this->link = ""; 
           $this->insideitem = false; 
       } 
   } 

   function characterData($parser, $data) { 
       if ($this->insideitem) { 
           switch ($this->tag) { 
               case "TITLE": 
               $this->title .= $data; 
               break; 
               case "DESCRIPTION": 
               $this->description .= $data; 
               break; 
               case "LINK": 
               $this->link .= $data; 
               break; 
           } 
       } 
   } 
} 

$xml_parser = xml_parser_create(); 
$rss_parser = new RSSParser(); 
xml_set_object($xml_parser,&$rss_parser); 
xml_set_element_handler($xml_parser, "startElement", "endElement"); 
xml_set_character_data_handler($xml_parser, "characterData"); 
$fp = fopen("http://www.lots-o-feeds.com/index.rdf","r") 
   or die("Error reading RSS data."); 
while ($data = fread($fp, 4096)) 
   xml_parse($xml_parser, $data, feof($fp)) 
       or die(sprintf("XML error: %s at line %d",  

           xml_error_string(xml_get_error_code($xml_parser)),  

           xml_get_current_line_number($xml_parser))); 
fclose($fp); 
xml_parser_free($xml_parser);

Funny thing is, I understand the code no problem - and it works like a dream - but I've never had call to use the notation %s and %d. It's obviously shorthand for "a string", but how does it work and where is it in the manual?

Thanks for your patience

Norm

[Weedpacket]

It comes from C programming, and the %thingies are short codes that describe how the variables that follow are to be formatted and inserted into the corresponding places in the string. The precise syntax (modified slightly to suit PHP) is described on the [man]sprintf[/man] page.

[Norman_Graham]

Thanks Weedpacket. That's very useful indeed.

Norm