PHP 获取数据两次

Question

我的函数看起来像那样。

 private function generateTree($courseID) {
        $q = "SELECT l.id, l.name AS lesson_name, c.name AS course_name FROM lessons AS l, courses AS c WHERE l.course_id=c.id AND c.id=?";
        $stmt = $this->db->prepare($q);
        $stmt->bind_param("i", $courseID);
        $stmt->execute();
        $stmt->store_result();
        if ($stmt->num_rows > 0) {
            $stmt->bind_result($id, $lName, $cName);
            echo "<li> <a href='#'>$cName</a> <ul>";
            while ($stmt->fetch()) <====HERE!!!
                echo "<li> <a href='?course=$courseID&lesson=$id'> $lName </a></li>";
            echo "</ul> </li>";
        }
    }

问题是我开始在 while 条件内获取数据，但在 while 之前我也需要它。我可以两次获取数据吗？还有其他建议吗？

Answer 1

已经四年了，但如果有人像我一样偶然发现这个问题:

while ($stmt->fetch()) {
  // do your thing
}

$stmt->data_seek(0);

while ($stmt->fetch()) {
  // do something other
}

您可以 read documentation here