添付ファイルの抽出と保存

すべての添付ファイルを取得

Aspose.PDFを使用すると、PDFドキュメントからすべての添付ファイルを取得できます。これは、PDFからドキュメントを別々に保存したい場合や、PDFから添付ファイルを削除する必要がある場合に便利です。

PDFファイルからすべての添付ファイルを取得するには：

1. DocumentオブジェクトのEmbeddedFilesコレクションをループします。EmbeddedFilesコレクションにはすべての添付ファイルが含まれています。このコレクションの各要素はFileSpecificationオブジェクトを表します。EmbeddedFilesコレクションを通じてのforeachループの各イテレーションはFileSpecificationオブジェクトを返します。
2. オブジェクトが利用可能になったら、添付ファイルのプロパティまたはファイル自体を取得します。

以下のコードスニペットは、PDFドキュメントからすべての添付ファイルを取得する方法を示しています。

以下のコードスニペットは、Aspose.PDF.Drawingライブラリでも動作します。

.NET Core 3.1

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void GetAllAttachments()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_Attachments();

    // Open PDF document
    using (var document = new Aspose.Pdf.Document(dataDir + "GetAlltheAttachments.pdf"))
    {
        // Get embedded files collection
        Aspose.Pdf.EmbeddedFileCollection embeddedFiles = document.EmbeddedFiles;

        // Get count of the embedded files
        Console.WriteLine("Total files : {0}", embeddedFiles.Count);

        int count = 1;

        // Loop through the collection to get all the attachments
        foreach (Aspose.Pdf.FileSpecification fileSpecification in embeddedFiles)
        {
            Console.WriteLine("Name: {0}", fileSpecification.Name);
            Console.WriteLine("Description: {0}",
            fileSpecification.Description);
            Console.WriteLine("Mime Type: {0}", fileSpecification.MIMEType);

            // Check if parameter object contains the parameters
            if (fileSpecification.Params != null)
            {
                Console.WriteLine("CheckSum: {0}",
                fileSpecification.Params.CheckSum);
                Console.WriteLine("Creation Date: {0}",
                fileSpecification.Params.CreationDate);
                Console.WriteLine("Modification Date: {0}",
                fileSpecification.Params.ModDate);
                Console.WriteLine("Size: {0}", fileSpecification.Params.Size);
            }

            // Get the attachment and write to file or stream
            var fileContent = new byte[fileSpecification.Contents.Length];
            fileSpecification.Contents.Read(fileContent, 0, fileContent.Length);
            using (var fileStream = new FileStream(dataDir + count + "_out" + ".txt", FileMode.Create))
            {
                fileStream.Write(fileContent, 0, fileContent.Length);
            }
            count += 1;
        }
    }
}

.NET 8

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void GetAllAttachments()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_Attachments();

    // Open PDF document
    using var document = new Aspose.Pdf.Document(dataDir + "GetAlltheAttachments.pdf");

    // Get embedded files collection
    Aspose.Pdf.EmbeddedFileCollection embeddedFiles = document.EmbeddedFiles;

    // Get count of the embedded files
    Console.WriteLine("Total files : {0}", embeddedFiles.Count);

    int count = 1;

    // Loop through the collection to get all the attachments
    foreach (Aspose.Pdf.FileSpecification fileSpecification in embeddedFiles)
    {
        Console.WriteLine("Name: {0}", fileSpecification.Name);
        Console.WriteLine("Description: {0}",
        fileSpecification.Description);
        Console.WriteLine("Mime Type: {0}", fileSpecification.MIMEType);

        // Check if parameter object contains the parameters
        if (fileSpecification.Params != null)
        {
            Console.WriteLine("CheckSum: {0}",
            fileSpecification.Params.CheckSum);
            Console.WriteLine("Creation Date: {0}",
            fileSpecification.Params.CreationDate);
            Console.WriteLine("Modification Date: {0}",
            fileSpecification.Params.ModDate);
            Console.WriteLine("Size: {0}", fileSpecification.Params.Size);
        }

        // Get the attachment and write to file or stream
        var fileContent = new byte[fileSpecification.Contents.Length];
        fileSpecification.Contents.Read(fileContent, 0, fileContent.Length);
        using var fileStream = new FileStream(dataDir + count + "_out" + ".txt", FileMode.Create);
        fileStream.Write(fileContent, 0, fileContent.Length);

        count += 1;
    }
}

個別の添付ファイルを取得

個別の添付ファイルを取得するには、DocumentインスタンスのEmbeddedFilesオブジェクト内の添付ファイルのインデックスを指定できます。以下のコードスニペットを使用してみてください。

.NET Core 3.1

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void GetIndividualAttachment()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_Attachments();

    // Open PDF document
    using (var document = new Aspose.Pdf.Document(dataDir + "GetIndividualAttachment.pdf"))
    {
        // Get particular embedded file
        Aspose.Pdf.FileSpecification fileSpecification = document.EmbeddedFiles[1];

        // Get the file properties
        Console.WriteLine("Name: {0}", fileSpecification.Name);
        Console.WriteLine("Description: {0}", fileSpecification.Description);
        Console.WriteLine("Mime Type: {0}", fileSpecification.MIMEType);

        // Check if parameter object contains the parameters
        if (fileSpecification.Params != null)
        {
            Console.WriteLine("CheckSum: {0}",
            fileSpecification.Params.CheckSum);
            Console.WriteLine("Creation Date: {0}",
            fileSpecification.Params.CreationDate);
            Console.WriteLine("Modification Date: {0}",
            fileSpecification.Params.ModDate);
            Console.WriteLine("Size: {0}", fileSpecification.Params.Size);
        }

        // Get the attachment and write to file or stream
        var fileContent = new byte[fileSpecification.Contents.Length];
        fileSpecification.Contents.Read(fileContent, 0, fileContent.Length);

        using (var fileStream = new FileStream(dataDir + "test_out" + ".txt", FileMode.Create))
        {
            fileStream.Write(fileContent, 0, fileContent.Length);
        }
    }
}

.NET 8

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void GetIndividualAttachment()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_Attachments();

    // Open PDF document
    using var document = new Aspose.Pdf.Document(dataDir + "GetIndividualAttachment.pdf");

    // Get particular embedded file
    Aspose.Pdf.FileSpecification fileSpecification = document.EmbeddedFiles[1];

    // Get the file properties
    Console.WriteLine("Name: {0}", fileSpecification.Name);
    Console.WriteLine("Description: {0}", fileSpecification.Description);
    Console.WriteLine("Mime Type: {0}", fileSpecification.MIMEType);

    // Check if parameter object contains the parameters
    if (fileSpecification.Params != null)
    {
        Console.WriteLine("CheckSum: {0}",
        fileSpecification.Params.CheckSum);
        Console.WriteLine("Creation Date: {0}",
        fileSpecification.Params.CreationDate);
        Console.WriteLine("Modification Date: {0}",
        fileSpecification.Params.ModDate);
        Console.WriteLine("Size: {0}", fileSpecification.Params.Size);
    }

    // Get the attachment and write to file or stream
    var fileContent = new byte[fileSpecification.Contents.Length];
    fileSpecification.Contents.Read(fileContent, 0, fileContent.Length);

    using var fileStream = new FileStream(dataDir + "test_out" + ".txt", FileMode.Create);
    fileStream.Write(fileContent, 0, fileContent.Length);
}

FileAttachmentAnnotationオブジェクトに含まれる添付ファイルを取得

DocumentオブジェクトのEmbeddedFilesコレクションに加えて、添付ファイルはFileAttachmentAnnotationオブジェクトにも含まれることがあります。以下は、そのような添付ファイルの数と詳細を表示するためのコードです。

.NET Core 3.1

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void ViewAttachmentsInFileAttachmentAnnotations()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_Attachments();

    // Open PDF document
    using (var document = new Aspose.Pdf.Document(dataDir + "GetAlltheAttachments.pdf"))
    {
        for (int i = 1; i <= document.Pages.Count; i++)
        {
            foreach (Aspose.Pdf.Annotations.Annotation annotation in document.Pages[i].Annotations)
            {
                var fileAttachmentAnnotation = annotation as Aspose.Pdf.Annotations.FileAttachmentAnnotation;
                if (fileAttachmentAnnotation != null)
                {
                    Aspose.Pdf.FileSpecification file = fileAttachmentAnnotation.File;
                    if (file != null && file.Name != null)
                    {
                        Console.WriteLine($"Name: {file.Name} on page {i}");
                    }
                }
            }
        }
    }
}

.NET 8

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void ViewAttachmentsInFileAttachmentAnnotations()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_Attachments();

    // Open PDF document
    using var document = new Aspose.Pdf.Document(dataDir + "GetAlltheAttachments.pdf");

    for (int i = 1; i <= document.Pages.Count; i++)
    {
        foreach (Aspose.Pdf.Annotations.Annotation annotation in document.Pages[i].Annotations)
        {
            var fileAttachmentAnnotation = annotation as Aspose.Pdf.Annotations.FileAttachmentAnnotation;
            if (fileAttachmentAnnotation != null)
            {
                Aspose.Pdf.FileSpecification file = fileAttachmentAnnotation.File;
                if (file != null && file.Name != null)
                {
                    Console.WriteLine($"Name: {file.Name} on page {i}");
                }
            }
        }
    }
}