Using cookies in ASP.NET MVC 5 project

Question

I'm trying to build a website that enables users to vote for things. The website works, but a user can vote multiple times. How can I prevent that?

I read online that I can use cookies. But I don't know how to implement them in my ASP.NET MVC 5 project.

Can you tell me how to use cookies for preventing multiple voting in ASP.NET MVC 5?

A small code snippet for starting would be great.

Doing so won't help much, cookies can easily be cleared by anyone. — Peter B, Apr 13 '16 at 09:09
If your problem is a homework assignment, then yes. Otherwise, it won't. — Peter B, Apr 13 '16 at 09:11
Using cookies will not be a good idea for your scenario. consider storing the userid and his vote cast information in database instead — Yogi, Apr 13 '16 at 09:14
You might find some ideas (but I don't know if they are better) here: http://stackoverflow.com/questions/572723/stopping-users-voting-multiple-times-on-a-website — Peter B, Apr 13 '16 at 09:15
Using cookies might not be the best idea. Users can delete the cookies. Having them make a profile, use an emailadres, limits the amount of votes. Maybe look at his IP adress (altough...) — Joren Vandamme, Apr 13 '16 at 09:27

Abhishek · Accepted Answer · 2016-04-13T11:56:25.337

<script>

    if (Cookies.get("HasAnswered") == 1) {
        $("#spn_Answered").text("Answered");
    }


    $("#btn_Answer").click(function (e) {
        e.preventDefault();
        if (Cookies.get("HasAnswered") == 1)
            alert("You have already answered the question");
        else {
            Cookies.set("HasAnswered", 1);
            $("#spn_Answered").text("Answered");
            alert("Congrats you have answered");
        }
    });

</script>

<html>
<head>
    <title>JS Cookie</title>
    <script type="text/javascript" src="//ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script>
    <script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/js-cookie/2.1.0/js.cookie.js"></script>
</head>
<body>
    <input type="button" name="" value="Answer Now" id="btn_Answer" />
    <span id="spn_Answered"></span>
</body>
</html>

1. You can use some sort of logic and place that in a cookie. Like

If user answered then mark the cookie value to 1 else make it 0.

Ex. Cookies.set('IsReplied', 1);

2. You can use this nice JS library. https://github.com/js-cookie/js-cookie

It provides a good documentation through which you can apply the cookies easily.

Hope this helps.

It is not working in stack overflow envoirement. There may be somthing missing. But the code is correct. copy and paste the code on your machine and it should work. — Abhishek, Apr 13 '16 at 11:59

Using cookies in ASP.NET MVC 5 project

1 Answers1