find option where value in jquery code example

Example 1: jquery select option by value

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

Example 2: get option value jquery

<select id="state">
    <option value="state1" data-id="1">state1</option>
    <option value="state2" data-id="2">state2</option>
    <option value="state3" data-id="3">state3</option>
</select>

$('#state option[data-id="2"]').val();

//output state2