Exporedt mysql数据不以Excel表格格式显示

Question

我使用下面给出的代码将数据库数据导出到Excel工作表，但导出数据正确＆amp; HTML代码也会显示

$Year="15";

$sql = "select * from table WHERE CurYear=$Year ORDER BY id"; 

$header = '';

$data ='';

$export = mysql_query($sql) or die(mysql_error($con));

while ($fieldinfo=mysql_fetch_field($export)){

    $header .= $fieldinfo->name."\t";
}

while( $row = mysql_fetch_row( $export ) ){

    $line = '';
    foreach( $row as $value )
    {                                            
        if ( ( !isset( $value ) ) || ( $value == "" ) )
        {
            $value = "\t";
        }
        else
        {
            $value = str_replace( '"' , '""' , $value );
            $value = '"' . $value . '"' . "\t";
        }
        $line .= $value;
    }
    $data .= trim( $line ) . "\n";
}

$data = str_replace( "\r" , "" , $data );

if ( $data == "" )
{

    $data = "\nNo Record(s) Found!\n";   

}

header("Content-type: application/octet-stream");

header("Content-Disposition: attachment; filename=export.xls");

header("Pragma: no-cache");

header("Expires: 0");

print "$header\n$data";