Set selected option to multiple list using jQuery

Question

I have a list from DB which is displayed in select multiple tags:

<select multiple="multiple" id="list" name="color">
  <option value="1">Red</option>
  <option value="2">Green</option>
  <option value="3">Blue</option>
  <option value="4">Magenta</option>
  <option value="5">Black</option>
  <option value="6">Cyan</option>
  <option value="7">Yellow</option>
</select>

Given an array of values from DB, need to select only those items that are found in the DB array, for example [2,4,7]. How do I push, with jQuery, attr('selected') to these option tags?

<select multiple="multiple" id="list" name="color">
  <option value="1">Red</option>
  <option value="2" selected="selected">Green</option>
  <option value="3">Blue</option>
  <option value="4" selected="selected">Magenta</option>
  <option value="5">Black</option>
  <option value="6">Cyan</option>
  <option value="7" selected="selected">Yellow</option>
</select>

Like above.

Answer 1

You've just to use the .val() method to achieve that :

$('#list').val([2,4,7]);

$('#list').val([2,4,7]);

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<select multiple="multiple" id="list" name="color">
  <option value="1">Red</option>
  <option value="2">Green</option>
  <option value="3">Blue</option>
  <option value="4">Magenta</option>
  <option value="5">Black</option>
  <option value="6">Cyan</option>
  <option value="7">Yellow</option>
</select>