php - PDO 中的 mysql_result

Question

下面是我的代码，都是用mysql写的。我正在尝试切换到 PDO。我的问题是，PDO 中的 mysql_result 相当于什么？

$query = "SELECT id, firstname, lastname FROM table";
if($mysql_query = mysql_query($query)){
    $id = mysql_result($mysql_query, 0, 'id');
    $firstname = mysql_result($mysql_query, 0, 'firstname');
    $lastname = mysql_result($mysql_query, 0, 'lastname');
}

到目前为止，我只能通过执行以下操作来执行 $query。

$query = $PDO -> prepare("SELECT id, firstname, lastname FROM table");
$query -> execute();

Answer 1

正如 Ian 上面所说的一种方式，或者如果您不使用准备功能，那么您可以这样做:

$sth = $PDO->query("SELECT id, firstname, lastname FROM table");

if ($sth->rowCount() > 1) {
    // One way to get the results if you have more then one row
    foreach ($sth as $row) {
        echo "ID: ".$row['id']."\n";
        echo "First name: ".$row['firstname']."\n";
        echo "Last name: ".$row['lastname']."\n";
    }
} elseif ($sth->rowCount() == 1) {
    // Or this way if you just have one row
    $result = $sth->fetch(PDO::FETCH_ASSOC);

    echo "ID: ".$result['id']."\n";
    echo "First name: ".$result['firstname']."\n";
    echo "Last name: ".$result['lastname']."\n";
}