สอบถามปัญหา ข้อมูล ARRAY ไม่เเสดงที่ Form ที่กำหนดไว้ครับ รบกวนทีครับ !!!!

<div class="container " style="width: 40%">
   
    <arm3>เลือกหมวดสินค้า </arm3><br><br>
    
    <select id="mySelect" onchange="myFunction()" style="width: 50%">
        <!--<option value="0">- เลือกหมวดสินค้า -</option>-->
        
  <?php
              include 'connectdbPHP.php';
              
              $sql = mysql_query("SELECT * FROM  tb_catalog ");
              
              $catalog = array();
                   
                    while ($row = mysql_fetch_array($sql)){
                        $catalog[] = $row;
                        
                         
                    }
                    
                     foreach ($catalog as $row) {
                          echo '<option value="'.$row['id_catalog'].'">'.$row['name_catalog'].'</option>';                            
                   }
        ?>
        
</select>

    <p id="id_catalog"></p><br>
    

</div>
<div class="container">
        
<div class="row"  >
                
                <table class="table table-striped table-bordered">
                  <thead>
                    <tr>
                        <th style="width: 400px"><center>รูปสินค้า</center></th>
                        <th ><center>ชื่อสินค้า</center></th>
                        <th style="width: 150px"><center>ราคา</center></th>
                
                    </tr>
                  </thead>
                </table>
    <?php
        include 'connectdbPHP.php';
     $sql = mysql_query("SELECT * FROM  tb_product where id_catalog ='1'");
                  
                   $product = array();
                   
                    while ($row = mysql_fetch_array($sql)){
                        $product[] = $row;
                        
                         
                    }
                    
                     foreach ($product as $row) {
                         
                            echo '<tr>';
                            echo '<td >'. $row['img_product'] . '</td>';
                            echo '<td>'. $row['name_product'] . '</td>';
                            echo '<td>'. $row['price_product'] . '</td>';
                            echo '</tr>';
                     }
    ?>
 </div>
    
</div>

<script>
function myFunction() {
    $id_catalog = document.getElementById("mySelect").value;
    document.getElementById("id_catalog").innerHTML = "You selected: " + $id_catalog;
}
</script>

 <arm3>เลือกหมวดสินค้า </arm3>
    
    <select id="mySelect" onchange="myFunction()" style="width: 50%">
        <!--<option value="0">- เลือกหมวดสินค้า -</option>-->
        
  <?php
              include 'connectdbPHP.php';
              
              $sql = mysql_query("SELECT * FROM  tb_catalog ");
              
              $catalog = array();
                   
                    while ($row = mysql_fetch_array($sql)){
                        $catalog[] = $row;
                        
                         
                    }
                    
                     foreach ($catalog as $row) {
                          echo '<option value="'.$row['id_catalog'].'">'.$row['name_catalog'].'</option>';                            
                   }
        ?>

<?php
        include 'connectdbPHP.php';
     $sql = mysql_query("SELECT * FROM  tb_product where id_catalog ='1'");
                  
                   $product = array();
                   
                    while ($row = mysql_fetch_array($sql)){
                        $product[] = $row;
                        
                         
                    }
                    
                     foreach ($product as $row) {
                         
                            echo '<tr>';
                            echo '<td >'. $row['img_product'] . '</td>';
                            echo '<td>'. $row['name_product'] . '</td>';
                            echo '<td>'. $row['price_product'] . '</td>';
                            echo '</tr>';
                     }
    ?>
                   </table>
 </div>
    
</div>

<script>
function myFunction() {
    $id_catalog = document.getElementById("mySelect").value;
    document.getElementById("id_catalog").innerHTML = "You selected: " + $id_catalog;
}
</script>