将MySQL表中的多个值提取为HTML

I want to get three values from a MYSQL table, and display them in a text area. I can get only one value. If it possible, I want to save this selector, because it is critical to my program.

JavaScript:

function getsteel() {
  var material = document.getElementsByName("option");
  if (material[3].checked == true) {
    var g = document.getElementById("selector1");
    var str = g.options[g.selectedIndex].value;
    document.getElementById('kr').value = str;
  }
}

HTML:

<td>k<sub>r</td></sub>
 <td>
    <input type="text" id="kr" disabled style="width:50px;">
  </td>
  <td>[MPa]</td>

PHP:

<?php
mysql_connect("localhost","root","");
mysql_select_db("db-user22777");
//query
$sql=mysql_query("SELECT * FROM steels ORDER BY id ASC");
if(mysql_num_rows($sql)){
  $select= '<select id="selector1" disabled size="12">';
  while($r=mysql_fetch_array($sql)){
    $select.='<option value="'.$r['kr'].'">'.$r['Steelname'].' | '.$r['kr'].' [MPa]</option>';
  } 
}
$select.='</select>';
echo $select;
?>

Thanks for any help provided!