Evercookie使用问题

Question

我发现很难获得由evercookie设置的cookie的值。

我想要做的只是检查是否设置了带有名称的evercookie。如果它没有被设置，那么我想将它设置为一个序号。

如下所示: var cookie_value = get_cookie_value；如果(cookie_value ==未定义)将coookie设置为"12345“，否则希望在php代码中使用它。

下面是来自http://samy.pl/evercookie/的Eveercoohie用法代码

var ec = new evercookie();  

// set a cookie "id" to "12345"
// usage: ec.set(key, value)
ec.set("id", "12345");

// retrieve a cookie called "id" (simply)
ec.get("id", function(value) { alert("Cookie value is " + value) });

// or use a more advanced callback function for getting our cookie
// the cookie value is the first param
// an object containing the different storage methods
// and returned cookie values is the second parameter
function getCookie(best_candidate, all_candidates)
{
    alert("The retrieved cookie is: " + best_candidate + "\n" +
        "You can see what each storage mechanism returned " +
        "by looping through the all_candidates object.");

    for (var item in all_candidates)
        document.write("Storage mechanism " + item +
            " returned " + all_candidates[item] + " votes<br>");
}
ec.get("id", getCookie);

// we look for "candidates" based off the number of "cookies" that
// come back matching since it's possible for mismatching cookies.
// the best candidate is very-very-likely the correct one

Answer 1

在本例中，cookie的名称是'id'，所以下面是如何在PHP中检查它的：

<?php
if (isset($_COOKIES['id'])) {
  //... cookie was set
} else {
  //... no cookie was set
  setcookie('id',$somenumber) ;
}
?>

不幸的是，这只会设置主要的HTTP cookie，而不是所有其他的evercookie元素。然而，在下一次刷新时，evercookie代码应该检测到它的一个元素包含一个值，并将所有其他元素设置为该相同的值。