PHP 查询数据库内的 Session_ID

Question

我一直在尝试在我的网站上查找 session ID，以便可以使用它来查询我的 MySQL 数据库，但我不断收到错误“ undefined variable :_SESSION in...”

这是我的代码:

if (mysql_num_rows(mysql_query("SELECT * FROM users WHERE _id = " . $_SESSION['_id_of_user'])))

这是我定义 session ID 的地方:

$qry = "Select name, email, username, _id from $this->tablename where username='$username' and password='$pwdmd5' and confirmcode='y'";

$result = mysql_query($qry,$this->connection);

if(!$result || mysql_num_rows($result) <= 0)
{
    $this->HandleError("Error logging in. The username or password does not match");
    return false;
}

$row = mysql_fetch_assoc($result);

$_SESSION['name_of_user']     = $row['name'];
$_SESSION['email_of_user']    = $row['email'];
$_SESSION['username_of_user'] = $row['username'];
$_SESSION['_id_of_user']      = $row['_id'];

Answer 1

您必须在 sql 查询之前启动 session : http://us.php.net/manual/en/function.session-start.php

session_start();

然后你应该通过以下方式获取当前 session ID: http://us.php.net/manual/en/function.session-id.php

$current_session_id = session_id();