Cookie returns undefined value in JavaScript -

i want make cookie remember radius user can choose. problem cookie works, value of cookie undefined. don't know doing wrong.

the function "opslaan" linked button on html page.

function opslaan() {     createcookie('radius',document.getelementbyid("range").value,8);     alert("opgeslagen"); }  function readcookie(name) {     var nameeq = name + "=";     var ca = document.cookie.split(';');     for(var i=0; < ca.length; i++) {         var c = ca[i];         while (c.charat(0)==' ')             c = c.substring(1,c.length);         if (c.indexof(nameeq) == 0)             return c.substring(nameeq.length,c.length);     }     return null; }  function createcookie(name,value,days) {     if (days) {         var date = new date();         date.settime(date.gettime() + (days*24*60*60*1000));         var expires = ";expires=" + date.togmtstring();     }     else         var expires = "";     document.cookie = name + "=" + value + expires +";path=/"; } 

this button , range field need value out:

<fieldset class="one-third column">     <label for="">radius van de kaart (km)</label>     <input type="range"            min="5"            max="20"            value="5"            step="5"            onchange="showvalue(this.value)" />     <span id="range">5</span>     <script type="text/javascript">         function showvalue(newvalue)         {             document.getelementbyid("range").innerhtml=newvalue;         }     </script> </fieldset> <script>     alert(readcookie('radius')); </script>  <div class="one-third column">     <a class="full-width button margin-top25"        href="home.html"         onclick="opslaan()">         opslaan     </a> </div> 

it seems working without range field , button.

in case range span not input element, need use innerhtml property read contents of element instead of using value.

use

document.getelementbyid("range").innerhtml 

instead of

document.getelementbyid("range").value 

ex:

function opslaan() {     createcookie('radius',document.getelementbyid("range").innerhtml,8); } 

demo: fiddle