select and option in jquery code example

Example 1: jqury get selected option

<select id="myselect">
    <option value="1">Mr</option>
    <option value="2">Mrs</option>
    <option value="3">Ms</option>
    <option value="4">Dr</option>
    <option value="5">Prof</option>
</select>

<script>
$( "#myselect option:selected" ).val();
</script>

Example 2: jquery select option by value

$('.id_100 option[value=val2]').attr('selected','selected');