Извлечение и сохранение вложения

Получить все вложения

С помощью Aspose.PDF можно получить все вложения из PDF-документа. Это полезно, когда вы хотите сохранить документы отдельно от PDF или если вам нужно удалить вложения из PDF.

Чтобы получить все вложения из PDF-файла:

1. Пройдите по коллекции EmbeddedFiles объекта Document. Коллекция EmbeddedFiles содержит все вложения. Каждый элемент этой коллекции представляет собой объект FileSpecification. Каждая итерация цикла foreach по коллекции EmbeddedFiles возвращает объект FileSpecification.
2. Как только объект доступен, извлеките либо все свойства прикрепленного файла, либо сам файл.

Следующие фрагменты кода показывают, как получить все вложения из PDF-документа.

Следующий фрагмент кода также работает с библиотекой Aspose.PDF.Drawing.

.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;
    }
}

Получить отдельное вложение

Чтобы получить отдельное вложение, мы можем указать индекс вложения в объекте EmbeddedFiles экземпляра документа. Пожалуйста, попробуйте использовать следующий фрагмент кода.

.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);
}

Получить вложения, содержащиеся в объектах FileAttachmentAnnotation

В дополнение к коллекции EmbeddedFiles объекта Document, вложения также могут содержаться в объектах FileAttachmentAnnotation. Ниже приведен код для просмотра количества и деталей таких вложений.

.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}");
                }
            }
        }
    }
}