How to use set_select on a multiple select box in codeigniter?

This is an example of multi select box in codeigniter

<select multiple class="form-control" name="city[]" id="city" style="height: 123px !important;">
         <?php $cities = getCitieslist();
         foreach ($cities as $city) {
         ?>
                  <option value="<?php echo $city->id?>" <?php if(@in_array($city->id, set_value('city[]'))): ?> selected="selected"<?php endif; ?>>
                         <?php echo  $city->fk_name.' - '.$city->description?>
                 </option>
<?php  } ?>
</select>


You can take a look above code or In simple code you can select the multiple value
<?php if(@in_array($city->id, set_value('city[]'))): ?> selected="selected"<?php endif; ?>

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