I am not able to display the selected value of my combobox

  <?php
echo "<select name=\"hello\">\n";
echo "<option value=\"NULL\">Select Value</option>\n";

   $strQuery = "select unitcode,unitname from units order by unitcode";
   $rsrcResult = mysql_query($strQuery);
$i=1;
$select='<select size=1 name="unitcode">';
   while($arrayRow = mysql_fetch_assoc($rsrcResult)) 
   {
     $strA = $arrayRow[$i];
      $strB = $arrayRow["unitcode"];
      $i=$i+1;
      echo "<option value=''>$strB</option>";
      $select.="<option name='unitcode'
value=\"".$myrow['$i']."\">".$myrow['name']."</option>\n";
$i=$i+1;
   }
   $number = $_POST['unitcode'];
echo "The number you selected was: '$number'"; ?>