用mysql和php打开pdf

Question

我将 pdf 存储在文件系统和数据库表中的路径上。我现在想根据 ID 在浏览器中打开对应的 PDF 文档。如何打开和阅读 PDF？ 我目前拥有的是这个

require_once("database.php");

if(isset($_GET['upload_id']) && is_numeric($_GET['upload_id']))
{
    $fileFolder='uploads/';

    $sql = "SELECT file FROM documents WHERE upload_id = :id"; 
    $result = $pdo->prepare($sql);
    $result->bindParam(":id", $_GET['upload_id']);
    $result->execute();                 

    $resArray = $result->fetchAll();

    $file = $resArray['file'];

    header('Pragma: public');
    header('Expires: 0');
    header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
    header('Content-Type: application/pdf');
    header('Content-Transfer-Encoding: binary');
    header('Content-Length: '.filesize($fileFolder.$file));
    @read($fileFolder.$file);

}

当我单击按钮并尝试打开 pdf 时，我在 Chrome 中收到了这条消息

无法加载 PDF 文档 重新加载

Answer 1

您可以使用fetch(PDO::FETCH_ASSOC); 获取文件名，它将下一行作为由column name 索引的数组返回

$sql = "SELECT file FROM documents WHERE upload_id = :id"; 
$result = $pdo->prepare($sql);
$result->bindParam(":id", $_GET['upload_id']);
$result->execute();     
$resArray = $result->fetch(PDO::FETCH_ASSOC);
$file = $resArray['file'];// get your file name

通过使用fetchAll

通过PDO::FETCH_COLUMN, 0

 $result = $sth->fetchAll(PDO::FETCH_COLUMN, 0);
 $file = $resArray[0];// get your file name

Answer 2

尝试以下方法：

require_once("database.php");

if(isset($_GET['upload_id']) && is_numeric($_GET['upload_id']))
{
    $fileFolder='uploads/';

    $sql = "SELECT file FROM documents WHERE upload_id = :id"; 
    $result = $pdo->prepare($sql);
    $result->bindParam(":id", $_GET['upload_id']);
    $result->execute();                 

    $resArray = $result->fetchAll();

    $file = $resArray['file'];

    $myFilePath = $fileFolder . $file;

    if (file_exists($myFilePath)) {

        // the file exists, so open it
        header('Pragma: public');
        header('Expires: 0');
        header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
        header('Content-Type: application/pdf');
        header('Content-Transfer-Encoding: binary');
        header('Content-Length: '.filesize($fileFolder.$file));
        @read($fileFolder.$file);

    } else {

        // the file doesn´t exits
        // handle the error if neccessary
        echo "the file doesn´t exist";

    }

}