jquery set select value

1$(document).ready(function() {
2    $("#gate option[value='Gateway 2']").prop('selected', true);
3    // you need to specify id of combo to set right combo, if more than one combo
4});
5

1$('select').on('change', function() {
2  alert( this.value );
3});

1$("#mySelectElementID").val("my_new_value"); //change selected option/value with jQuery
2

1$("div.id_100 select").val("val2");
2