<? 
/**
 * PHP相对路径转换成绝对路径
 *
 * @param 
 * @author 编程之家 jb51.cc jb51.cc
 **/
function relative_to_absolute($content,$Feed_url) {  
	preg_match('/(http|https|ftp):///',$Feed_url,$protocol);  
	$server_url = preg_replace("/(http|https|ftp|news):///","",$Feed_url);  
	$server_url = preg_replace("//.*/",$server_url); 
	if ($server_url == '') {  
		return $content;  
	} 
	if (isset($protocol[0])) {
		$new_content = preg_replace('/href="//','href="'.$protocol[0].$server_url.'/',$content);  
		$new_content = preg_replace('/src="//','src="'.$protocol[0].$server_url.'/',$new_content);  
	} else {  
		$new_content = $content;  
	}  
	return $new_content;  
} 
/***   来自编程之家 jb51.cc（jb51.cc）   ***/