Javascript/jQuery: ensuring unique option added to pulldown -

i have html pulldown menu along text element allows users add new options menu. i'd make sure every option added unique. following 2 lines first option thought of worked (option value = innhtml of options). i'm wondering if there's more elegant solution -- second line seems clunky. doesn't handle spaces in new_name string.

var new_name = document.getelementbyid("preset_name").value var unique_name = $("option[value="+new_name+"]").length === 0 ? true : false  

do need this?

html:

<select id="myselect">   <option value="volvo">volvo</option>   <option value="saab">saab</option>   <option value="mercedes">mercedes</option>   <option value="audi">audi</option> </select>  <input id="newoption" type="text" /> <button id="check">check</button> 

jquery:

$(document).ready(function() {     $("button#check").click(function() {         var newopt = $("input#newoption").val();         $("#myselect option").each(function(){             var text = $(this).val();             if(newopt.length>0 && text.indexof(newopt)!=-1){                 console.log("already present!");             }         });     }); }); 

jsfiddle