Php 使用Laravel上载和显示保存在PostgreSQL中的PDF文件

我有一个项目，要求我在数据库中保存PDF文件（将文件保存在数据库中，而不是路径）。我正在使用PostgreSQL 10和Laravel 5.6。这是我的迁移文件：

public function up()
{
    Schema::create('uploads', function (Blueprint $table) {
        $table->increments('id');
        $table->string('name');
        $table->string('mime');
        $table->binary('data'); // generate a bytea column after running migration
        $table->timestamps();
    });
}

Schema::create('uploads', function (Blueprint $table) {
        $table->increments('id');
        $table->string('name');
        $table->string('mime');
        $table->text('data');
        $table->timestamps();
});

下面是我的控制器中上载PDF文件的功能：

public function upload(Request $req)
{
  $name = pg_escape_string($_FILES['fpdf']['name']);
  $type = pg_escape_string($_FILES['fpdf']['type']);
  $data = pg_escape_bytea(file_get_contents($_FILES['fpdf']['tmp_name']));

  DB::table('uploads')
  ->insert(['name' => $name, 'mime' => $type, 'data' => $data]);

  return "success upload";
}

public function upload()
{
    $name = $_FILES['fpdf']['name'];
    $mime = $_FILES['fpdf']['type'];
    $content = base64_encode(file_get_contents($_FILES['fpdf'['tmp_name']));

    $up = new Upload;

    $up->name = $name;
    $up->mime = $mime;
    $up->content = $content;

    $up->save();

    return redirect('upload');
}

public function showPDF($id)
{
    $pdf = Upload::find($id);

    $content = base64_decode($pdf->content);
    return response($content)->header('Content-Type', $pdf->mime); // thanks to Devon
}

已成功上载PDF文件：

但问题是，无法在浏览器中显示（下载）PDF文件。这是我的控制器中用于在浏览器中显示PDF文件的功能：

public function showPDF($id)
{
  $pdf = Upload::find($id);
  return view('upload/pdf', compact('pdf'));
}

查看文件：

<?php
    $content = pg_unescape_bytea(stream_get_contents($pdf->data));
    echo "<embed src='data:". $pdf->mime .";base64,".base64_encode($content)."' />";
?>

---

现在大多数浏览器都内置了PDF阅读器，通常没有理由使用embed，除非你真的想将PDF嵌入到其他内容中

为此，您应该能够从控制器返回响应，并为内容类型设置标题：

return response($content)->header('Content-Type', $pdf->mime);

---

在尝试了几种组合后，我找到了解决方案。以下是我的解决方案：

迁移文件：

public function up()
{
    Schema::create('uploads', function (Blueprint $table) {
        $table->increments('id');
        $table->string('name');
        $table->string('mime');
        $table->binary('data'); // generate a bytea column after running migration
        $table->timestamps();
    });
}

Schema::create('uploads', function (Blueprint $table) {
        $table->increments('id');
        $table->string('name');
        $table->string('mime');
        $table->text('data');
        $table->timestamps();
});

我在迁移文件中所做的是更改列数据的数据类型，以前我使用的是二进制，这里我使用的是文本

“我的控制器”中用于上载PDF文件的函数：

public function upload(Request $req)
{
  $name = pg_escape_string($_FILES['fpdf']['name']);
  $type = pg_escape_string($_FILES['fpdf']['type']);
  $data = pg_escape_bytea(file_get_contents($_FILES['fpdf']['tmp_name']));

  DB::table('uploads')
  ->insert(['name' => $name, 'mime' => $type, 'data' => $data]);

  return "success upload";
}

public function upload()
{
    $name = $_FILES['fpdf']['name'];
    $mime = $_FILES['fpdf']['type'];
    $content = base64_encode(file_get_contents($_FILES['fpdf'['tmp_name']));

    $up = new Upload;

    $up->name = $name;
    $up->mime = $mime;
    $up->content = $content;

    $up->save();

    return redirect('upload');
}

public function showPDF($id)
{
    $pdf = Upload::find($id);

    $content = base64_decode($pdf->content);
    return response($content)->header('Content-Type', $pdf->mime); // thanks to Devon
}

我使用base64\u encode（）函数对PDF文件进行编码。下面是显示PDF文件的方法：

public function upload(Request $req)
{
  $name = pg_escape_string($_FILES['fpdf']['name']);
  $type = pg_escape_string($_FILES['fpdf']['type']);
  $data = pg_escape_bytea(file_get_contents($_FILES['fpdf']['tmp_name']));

  DB::table('uploads')
  ->insert(['name' => $name, 'mime' => $type, 'data' => $data]);

  return "success upload";
}

public function upload()
{
    $name = $_FILES['fpdf']['name'];
    $mime = $_FILES['fpdf']['type'];
    $content = base64_encode(file_get_contents($_FILES['fpdf'['tmp_name']));

    $up = new Upload;

    $up->name = $name;
    $up->mime = $mime;
    $up->content = $content;

    $up->save();

    return redirect('upload');
}

public function showPDF($id)
{
    $pdf = Upload::find($id);

    $content = base64_decode($pdf->content);
    return response($content)->header('Content-Type', $pdf->mime); // thanks to Devon
}

查看文件：

<!DOCTYPE html>
<html lang="en" dir="ltr">
<head>
    <meta charset="utf-8">
    <title>Demo Upload</title>
</head>
<body>
    <h1>Form Upload PDF File</h1>

    <form action="upload" method="post" enctype="multipart/form-data">
        @csrf

        <br>
        <input type="file" name="fpdf">
        <br> <br>
        <input type="submit" value="Upload">
    </form>

    <p>&nbsp;</p>

    <h3>List of PDFs</h3>

    @foreach($pdfs as $row)
        <a href="show/{{ $row->id }}" target="_blank"> {{ $row->name }} </a>
        <br>
    @endforeach
</body>
</html>

演示上传
表格上传PDF文件
@csrf






PDF文件列表
@foreach（$PDF作为$row）


@endforeach

---

这是我目前的解决方案。我知道这可能不是处理文件上传的最佳方式，但它确实有效。欢迎提出任何使代码更好、更安全的建议。

为什么要使用转义字符串函数？你真的想嵌入它还是让他们下载它？嗨，德文，我想做任何一个，但我更喜欢下载PDF文件。你真的不应该把pg_uuu函数和Laravel结合起来。无论如何，停止使用转义字符串函数，即使在Laravel之外，您也应该使用准备好的语句。我在showPDF函数中尝试了您的代码，但它给了我一个错误：响应内容必须是实现u toString（）、给定“resource”的字符串或对象。我修改了showPDF函数，但现在加载PDF文档失败（以上问题的详细信息）。我遗漏了什么？您的第一条消息表明$content不是字符串。