How to fix XML declaration allowed only at the start of the document

[Comp90]

Hi:

I want to make a dynamic sitemap . this is my code that was written with class

but show this error:

This page contains the following errors:

error on line 2 at column 6: XML declaration allowed only at the start of the document
Below is a rendering of the page up to the first error.

<?php
class googlemap{
	var $home = patch_url;
	var $limit = 10;
	var $news_priority = "0.5";
	var $stat_priority = "0.5";
	var $priority = "0.6";
	var $cat_priority = "0.7";
	function googlemap () {


	}

	function build_map () {

		$map  = "<?xml version='1.0' encoding='UTF-8'?><urlset xmlns='http://www.sitemaps.org/schemas/sitemap/0.9'>";
		$map .= $this->get_static();
		
		
		$map .= "</urlset>";

		return $map;

	}
	

	function get_static() {

		global $class_db;
		if ($this->limit < 1) $this->limit = false;

		if ($this->limit) {

			$this->limit = " LIMIT 0,".$this->limit;

		} else {

			$this->limit = "";

		}
		$xml = "";
		$lastmod=date("Y-m-d");

		$this->priority = $this->stat_priority;

		$my_sql_info = $class_db->sql_query("SELECT * FROM `".dbperfix."page_name`   ORDER BY `id` DESC  ".$this->limit ."");
		$n=0;
		while($my_sql_info_r = $class_db->sql_fetchrow( $my_sql_info ) ){

			$loc = $this->home.'/fa/fullmode/page/'.$my_sql_info_r['url'].'.html';

			$xml .= $this->get_xml($loc, $lastmod);
		}

		return $xml;
	}
	function get_xml($loc, $lastmod){

		$loc = htmlspecialchars($loc);

		$xml = "\t<url>\n";
		$xml .= "\t\t<loc>$loc</loc>\n";
		$xml .= "\t\t<lastmod>$lastmod</lastmod>\n";
		$xml .= "\t\t<priority>".$this->priority."</priority>\n";
		$xml .= "\t</url>\n";

		return $xml;
	}

}
?>

[Dormilich]

it would help to see the generated XML. because there is something on line one that is not from this code.

[Comp90]

befor this code run this code in sitemap.php:

<?
ob_start( );

include('include/conf.php');
include('include/function.php');
include('include/class_db.php');
include('include/function_time_new.php');
header('Content-Type: text/xml');
include_once('include/class_googlemap.php');
$map = new googlemap();
$map->home =patch_url;
$sitemap = $map->build_map();
print $sitemap;
ob_end_flush();
?>

[Dormilich]

it still would help to see the generated XML.