php_select_box_with_other_option.php

<?
// Written for my own use, 2009


function select_exisiting_or_new($object,$field_name){
  // To use:
  // echo select_exisiting_or_new($product,'manufacturer')?
  
  $current_value = $object->$field_name;
  $possible_values = $object->query("SELECT `$field_name` from $object->table_name GROUP BY `$field_name` ORDER BY `$field_name`");

  ob_start();
  ?>
  <select 
  name="<?=htmlspecialchars($field_name)?>" 
  onchange="var show_new = (this.selectedIndex==this.options.length-1); var new_field=document.getElementById('field_<?=htmlspecialchars($field_name)?>_extra'); new_field.style.display=(show_new?'inline':'none'); new_field.disabled=(show_new?false:true); if(show_new){new_field.focus()}" 
  id="field_<?=htmlspecialchars($field_name)?>">
    <option value="">-- Choose One--</option>
    <?php foreach ($possible_values as $pvalue): 
      $value = $pvalue->$field_name;
      if($value==''){ continue; }
      $checked = $value == $current_value ? 'selected' : '';
      ?>
      <option <?=$checked?>><?=htmlspecialchars($value)?></option>
    <?php endforeach ?>
    <option value="">Add new...</option>
  </select>
  <input type="text" value="" name="<?=htmlspecialchars($field_name)?>" id="field_<?=htmlspecialchars($field_name)?>_extra" style="display:none" disabled="true">
  <?
  
  return ob_get_clean();
}

?>