How to pick up an existing cookie via javascript

Question

In my project I have a page that is html. And since my project is in Asp.net mvc, I can’t validate whether the user is logged in or not because this page is not Razor.

Researching, I found the javascript cookie, that creates, reads and deletes cookies. So basically, I already have one cookie created and what I wanted was that the javascript cookie take that cookie make a validation to see if there is a cookie, if not, redirect to the login.

So far I have this code:

  <script>
    function getCookie(cname) {
        var name = cname + "=";
        var ca = window.document.cookie.split(';');
        for (var i = 0; i < ca.length; i++) {
            var c = ca[i];
            while (c.charAt(0) == ' ') c = c.substring(1);
            if (c.indexOf(name) != -1) return c.substring(name.length, c.length);
        }
        return "";
    }
    function checkCookie() {
        var permissao = getCookie(".PermissionCookie");
        if (permissao == "") {
            alert("Oooops! Você não tem permissão!");
            window.location.replace("/Index/Autenticacao")

        }
    }

</script>

But it’s not working...

Remembering that I want this check to be done as soon as the page loads.

What can I do to make it work ?

Answer 1

To make an AJAX jquery request, create a "checkAccess.js" file, or something like and put it in the include of your page.

 $(document).ready(function(){
   $.get("http://www.seusite.com.br/pagina.asp", function(data, status){
     alert("Data: " + data + "\nStatus: " + status);
   });
 });

On this page of yours, you replace the Page_Load by a Response.Write with true/false (even a string) and ready:

 string json = "{\"logado\":\"true\"}";
 Response.Clear();
 Response.ContentType = "application/json; charset=utf-8";
 Response.Write(json);
 Response.End();

Cookies seem a little complicated to me. You can even remove some of them, but I think the internet explorer will be warning that your site has an Activex component (javascript) trying to do something suspicious. I don’t remember which versions, but if the user does not accept, your javascript will be useless.

Already the jquery is better.

If the session is falling (the guy is spending too much time on multiple HTML pages) and is dropping, it is best to put one <img href="http://www.seusite.com.br/img.gif" /> with a 1px gif per 1px transparent... this should be enough to keep the session active.

I still find it very unsafe, but I don’t know what the status of your project as a whole.