Question

我很难使用isset（）函数。究竟如何告诉php，只有数据被分配给我，让我们说$ _SESSION ['msg'];变量，然后才激活它并使用它...到目前为止，我收到了很多通知：未定义索引，此代码也没有这样做：

if (isset($_SESSION['monster']) &
isset($_SESSION['spol']) &  
isset($_SESSION['combat']) &
isset($_SESSION['turns']) &  
isset($_SESSION['zmaga']) &
isset($_SESSION['zguba']) &
isset($_SESSION['cekini']) &
isset($_SESSION['post']) )

{
$monster = $_SESSION['monster'];
$spol = $_SESSION['spol'];
$combat = $_SESSION['combat'];
$turns = $_SESSION['turns'];
$zmaga = $_SESSION['zmaga'];
$zguba = $_SESSION['zguba'];
$cekini = $_SESSION['cekini'];
$_POST = $_SESSION['post'];
}

数据应该是从重定向的上一个站点取而代之的，但该站点并不总是激活，所以我需要一个替代方案。这就是我问这个的原因。

编辑完整代码：

session_start();

include 'razno.php';
include 'save.php';
include 'stats.php';

$igralec_ime = $_SESSION['username'];
$monster = prikazi_borba($igralec_ime);
$poskodbe = prikazi_stat('curhp', $igralec_ime);

if (prikazi_stat('curhp', $igralec_ime) == 0)
{
$moznost = 'Tvoje zdravje je resno ogroženo, vrni se domov!';
}

else if (isset($_SESSION['monster']) &&
isset($_SESSION['spol']) &&  
isset($_SESSION['combat']) &&
isset($_SESSION['turns']) &&  
isset($_SESSION['zmaga']) &&
isset($_SESSION['zguba']) &&
isset($_SESSION['cekini']) &&
isset($_SESSION['post']) )
{
$monster = $_SESSION['monster'];
$spol = $_SESSION['spol'];
$combat = $_SESSION['combat'];
$turns = $_SESSION['turns'];
$zmaga = $_SESSION['zmaga'];
$zguba = $_SESSION['zguba'];
$cekini = $_SESSION['cekini'];
$_POST = $_SESSION['post'];

}

update_save($igralec_ime, 'gozd', $monster);

include '../html/gozd.html';
?>

Answer 1

你想要替换＆amp;用和：

if (isset($_SESSION['monster']) and isset($_SESSION['spol']) and isset($_SESSION['combat']) and isset($_SESSION['turns']) and isset($_SESSION['zmaga']) and isset($_SESSION['zguba']) &
isset($_SESSION['cekini']) and isset($_SESSION['post']) )

{
$monster = $_SESSION['monster'];
$spol = $_SESSION['spol'];
$combat = $_SESSION['combat'];
$turns = $_SESSION['turns'];
$zmaga = $_SESSION['zmaga'];
$zguba = $_SESSION['zguba'];
$cekini = $_SESSION['cekini'];
$_POST = $_SESSION['post'];
}

Answer 2

您应该在PHP中查看logical operators。在许多编程语言中（包括PHP）&是'按位和'运算符（非逻辑）。由于您需要逻辑运算符，因此您需要使用&&或and。另外看看其他PHP操作符，只是为了熟悉它们并避免这样的问题。

此外，如果您在if / then块之外使用这些值，您应该考虑语句为false的情况，并为这些变量分配一些默认值。

如果设置了变量，则显示$ _SESSION数据

2 个答案: