导出到php mysql中的excel问题

Im using this code for export table data to excel. I have been trying this it just displaying the data on the screen, do i need to do any modification. Im not able to see the file, dont even have any idea whether it is exporting to file or not. I guess it is not doing any thing rather than displaying data on the screen.

$q = "SELECT * FROM myrecords";
$qr = mysql_query( $q ) or die( mysql_error() );


// Ok now we are going to send some headers so that this
// thing that we are going make comes out of browser
// as an xls file.
//
header("Pragma: public");
header("Expires: 0");
header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
header("Content-Type: application/force-download");
header("Content-Type: application/octet-stream");
header("Content-Type: application/download");

//this line is important its makes the file name
header("Content-Disposition: attachment;filename=export_file.xls ");

header("Content-Transfer-Encoding: binary ");

// start the file
xlsBOF();

// these will be used for keeping things in order.
$col = 0;
$row = 0;

// This tells us that we are on the first row
$first = true;

while( $qrow = mysql_fetch_assoc( $qr ) )
{
// Ok we are on the first row
// lets make some headers of sorts
if( $first )
{
foreach( $qrow as $k => $v )
{
// take the key and make label
// make it uppper case and replace _ with ' '
xlsWriteLabel( $row, $col, strtoupper( ereg_replace( "_" , " " , $k ) ) );
$col++;
}

// prepare for the first real data row
$col = 0;
$row++;
$first = false;
}

// go through the data
foreach( $qrow as $k => $v )
{
// write it out
xlsWriteLabel( $row, $col, $v );
$col++;
}
// reset col and goto next row
$col = 0;
$row++;
}

xlsEOF();
exit();

Please suggest any modification required?