<select name="leixing" id="leixing" >
              <option value="">選擇型別</option>
              <?php
                 $result_1=mysql_query("select * from leixing");
                 while($row_1=mysql_fetch_array($result_1)){
                 $leixing_1=$row_1["leixing"];
                 $id_1=$row_1["id"];
    
                 if ($id_1==$myrow["leixing"]) {
                          echo "<option value=$id_1 selected>$leixing_1</option>";
                 }

                 else{
                         echo "<option value=$id_1>$leixing_1</option>";
                 }
                 }

                mysql_close($conn);
            ?>
 </select>