Set the selected index of a Dropdown using jQuery

First of all – that selector is pretty slow. It will scan every DOM element looking for the ids. It will be less of a performance hit if you can assign a class to the element.

$(".myselect")

To answer your question though, there are a few ways to change the select elements value in jQuery

// sets selected index of a select box to the option with the value "0"
$("select#elem").val('0'); 

// sets selected index of a select box to the option with the value ""
$("select#elem").val(''); 

// sets selected index to first item using the DOM
$("select#elem")[0].selectedIndex = 0;

// sets selected index to first item using jQuery (can work on multiple elements)
$("select#elem").prop('selectedIndex', 0);