Hello every body,

when i select some options, i want to keep it disabled after submit and after refresh/return on the page.

I write this code:

<!DOCTYPE html>
<html lang="en">
<meta charset="utf-8">
<title>Checkbox answer</title>

	function checks()
			var i;
		   var select = document.getElementById("sel");
   		   options = select.getElementsByTagName("option");
  		   values  = [];
    for (i=0; i<options.length; i++)
        if (options[i].selected) 
       		localStorage.setItem("values", values);
       			if (localStorage.getItem("values")) 
   				 select.options[localStorage.getItem("values")].disabled = true;

<form action= # onsubmit="return checks()">

<select name="seating position" id= "sel" multiple >
  <option value="1" >seat1</option>
 <option value="2">seat2</option>
 <option value="3">seat3</option>
 <option value="4">seat4</option>
<option value="5">seat5</option>
<option value="6">seat6</option>
<option value="7">seat7</option>
<option value="8">seat8</option>
<option value="9">seat9</option>
<option value="10">seat10</option>
<input type="submit" value = "OK">

What is wrong? Thank you