session storage

session storage

Hello i'm using html5 & jquery 
and i look how can save my session with sessionStorage 
i'm using 3 inputs [ text/password/checkbox]
i want when i check the checkbox my session will be saved for example i close my browser and open it 
it open with my session but i can't do this 
this my code 

$(document).ready(function() {
$('#submit').click(function(){ 
//\\
var fieldValue = document.getElementById('username').value;
sessionStorage.setItem('username', fieldValue);
var fieldValue = document.getElementById('password').value;
sessionStorage.setItem('password', fieldValue);

//\\
});
$('#disconnect').click(function(){
//\\
document.getElementById('username').value='';
sessionStorage.removeItem('username');
document.getElementById('password').value='';
sessionStorage.removeItem('password');
//\\
});
});