Best way to determine if cookies are enabled in ASP.NET? - asp.net

Question

What is the best method for determining if a users browser has cookies enabled in ASP.NET

Answer 1

Set a cookie, force a redirect to some checking page and check the cookie.
Or set a cookie on every pageload, if it's not already set. For instance, I assume this is to check if cookies are supported to display a message when they try to login that they need to enable cookies. Set your login cookie to some default value for guest users if they don't have the cookie set yet. Then on your login page, check for the user cookie, and if it's not set, then display your message.

Answer 2

#Mattew is right the only way to find out is to set a cookie, redirect, then check it.
Here is a C# function to preform that check you can put this in your page load event:
private bool cookiesAreEnabled()
{
bool cookieEnabled = false;
if(Request.Browser.Cookies)
{
//Your Browser supports cookies
if (Request.QueryString["TestingCookie"] == null)
{
//not testing the cookie so create it
HttpCookie cookie = new HttpCookie("CookieTest","");
Response.Cookies.Add(cookie);
//redirect to same page because the cookie will be written to the client computer,
//only upon sending the response back from the server
Response.Redirect("Default.aspx?TestingCookie=1")
}
else
{
//let's check if Cookies are enabled
if(Request.Cookies["CookieTest"] == null)
{
//Cookies are disabled
}
else
{
//Cookies are enabled
cookieEnabled = true;
}
}
}
else
{
// Your Browser does not support cookies
}
return cookieEnabled;
}
You can do it in javascript also, this way :
function cookiesAreEnabled()
{
var cookieEnabled = (navigator.cookieEnabled) ? 1 : 0;
if (typeof navigator.cookieEnabled == "undefined" && cookieEnabled == 0){
document.cookie="testcookie";
cookieEnabled = (document.cookie.indexOf("test­cookie") != -1) ? 1 : 0;
}
return cookieEnabled == 1;
}

Answer 3

Write a cookie, redirect, see if you can read the cookie.

Answer 4

Well I think if we can save cookie in Global.ASAX session start and read that on page.. isnt that best way?

Answer 5

Essentially the same solution as meda, but in VB.NET:
Private Function IsCookieDisabled() As Boolean
Dim currentUrl As String = Request.RawUrl
If Request.Browser.Cookies Then
'Your Browser supports cookies
If Request.QueryString("cc") Is Nothing Then
'not testing the cookie so create it
Dim c As HttpCookie = New HttpCookie("SupportCookies", "true")
Response.Cookies.Add(c)
If currentUrl.IndexOf("?") > 0 Then
currentUrl = currentUrl + "&cc=true"
Else
currentUrl = currentUrl + "?cc=true"
End If
Response.Redirect(currentUrl)
Else
'let's check if Cookies are enabled
If Request.Cookies("SupportCookies") Is Nothing Then
'Cookies are disabled
Return True
Else
'Cookies are enabled
Return False
End If
End If
Else
Return True
End If
End Function

Answer 6

meda's c# function works though you have to change the line:
HttpCookie cookie = new HttpCookie("","");
to
HttpCookie cookie = new HttpCookie("CookieTest","CookieTest");

Answer 7

You can also check the value of Request.Browser.Cookies. If true, the browser supports cookies.

Answer 8

this is the best way
taken from
http://www.eggheadcafe.com/community/aspnet/7/42769/cookies-enabled-or-not-.aspx
function cc()
{
/* check for a cookie */
if (document.cookie == "")
{
/* if a cookie is not found - alert user -
change cookieexists field value to false */
alert("COOKIES need to be enabled!");
/* If the user has Cookies disabled an alert will let him know
that cookies need to be enabled to log on.*/
document.Form1.cookieexists.value ="false"
} else {
/* this sets the value to true and nothing else will happen,
the user will be able to log on*/
document.Form1.cookieexists.value ="true"
}
}
thanks to Venkat K