php - 从 PHP 表的列中检索选定的值

Question

如何从 VBmembers 表中检索“level”列的选定值并将其设置为 $level 变量？

    session_start();

if (isset($_SESSION['user']))
{
    $user = $_SESSION['user'];
    $query = "SELECT level FROM VBmembers WHERE user='$user'";
    $level = queryMysql($query);
    $loggedin = TRUE;
}
else $loggedin = FALSE;

queryMysql函数代码

function queryMysql($query)
{
    $result = mysql_query($query) or die ('ivalid query: ' . mysql_error());
    return $result;
}

Answer 1

您还需要几个步骤，最重要的是从结果中以可用的方式获取数据:

$user = $_SESSION['user'];
$query = "SELECT level FROM VBmembers WHERE user='$user'";
$result = queryMysql($query);
$row = mysql_fetch_array($result);
$level = $row['level'];
$loggedin = TRUE;

正如我在评论中所说，your script is at risk for SQL Injection Attacks.

如果可以的话，你应该stop using mysql_* functions 。 These extensions已在 PHP 7 中删除。了解 prepared PDO 的声明和 MySQLi并考虑使用 PDO，it's really not hard .