ส่ง querystring แบบ post ผ่าน URL แล้ว echo ตัวแปรไม่มาด้วยครับ

<?php
$ids = $_POST['id'];
if (is_array($ids)) {
    foreach ($ids as $id) {
        echo $id.'<br>';// id แต่ละ form field จะได้ตรงนี้
    }
}
?>

 <?php 
    $id = $_POST['id'];
    $id = htmlspecialchars($_POST['id']);
    $machineborrow = $db->prepare('SELECT mName,id
                                     FROM tbl_machine 
                                     WHERE id = :id' );
      $machineborrow->bindParam(':id',$id,PDO::PARAM_STR);
      $machineborrow->execute();
      while($row = $machineborrow->fetch(PDO::FETCH_ASSOC)){
    ?>
    <div class="col-md-6 col-md-offset-1">
      <blockquote>
        <p>รหัสเครื่อง: <?=$row['id']; ?> &nbsp; ชื่อเครื่อง: <?=$row['mName'];?></p>
      </blockquote>
    </div>
   </div>
<?php } ?>

<form name="frmMenu1" action="Machineborrowform.php?id=<?php echo $row['id']; ?>" method="POST">
<div id="menu1" class="tab-pane fade">
    	<?php
    	
                  $machine = $db->query('SELECT mType,mName,id
                                           FROM  tbl_machine 
                                           WHERE mType = 2
                                           ORDER BY mName');
                  $machine->execute();
      	
            while($row = $machine->fetch(PDO::FETCH_ASSOC)) {
              //$_SESSION['id'] = $row['id'];
      	?>
      		<div class="col-sm-2 col-md-2" style="padding-top: 1cm;" >
    			<div class="thumbnail">
      				<img src="image/My-Computer-icon.png" alt="...">
      			<div class="caption">
        			<h5><?=$row['mName'];?></h5>
        			<p>...</p>
        			<p><button type="submit" class="btn btn-primary">ยืม</button> <a href="#" class="btn btn-default" role="button">คืน</a></p>
             
      			</div>
    			</div>
  			</div>
<?php 
} 
?>
    </div> <!-- menu1-->
</form>
     

<form name="frmMenu1" action="Machineborrowform.php?id=<?php echo $row['id']; ?>" method="POST">

<form name="frmMenu1" action="Machineborrowform.php?Mid=VCD01" method="GET">

<input type="hidden" name="hdnID[]" value="<?php echo $row['id']; ?>">

foreach ($_POST['hdnID'] as $key => $value) {
    echo $value. "<br />";
}

$machine=$db->query('....');
// $machine->execute() ;