使用 C# 创建带标签的 PDF

创建带标签的 PDF 意味着向文档添加（或创建）某些元素，以使文档能够根据 PDF/UA 要求进行验证。这些元素通常称为结构元素。

以下代码片段也适用于 Aspose.PDF.Drawing 库。

创建带标签的 PDF（简单场景）

为了在带标签的 PDF 文档中创建结构元素，Aspose.PDF 提供了使用 ITaggedContent 接口创建结构元素的方法。以下代码片段展示了如何创建包含 2 个元素的带标签 PDF：标题和段落。

.NET Core 3.1

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void CreateTaggedPdfDocument01()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();

    // Create PDF document
    using (var document = new Aspose.Pdf.Document())
    {
        // Get Content for work with TaggedPdf
        Aspose.Pdf.Tagged.ITaggedContent taggedContent = document.TaggedContent;
        var rootElement = taggedContent.RootElement;

        // Set Title and Language for Document
        taggedContent.SetTitle("Tagged Pdf Document");
        taggedContent.SetLanguage("en-US");

        Aspose.Pdf.LogicalStructure.HeaderElement mainHeader = taggedContent.CreateHeaderElement();
        mainHeader.SetText("Main Header");

        Aspose.Pdf.LogicalStructure.ParagraphElement paragraphElement = taggedContent.CreateParagraphElement();
        paragraphElement.SetText("Lorem ipsum dolor sit amet, consectetur adipiscing elit. " +
            "Aenean nec lectus ac sem faucibus imperdiet. Sed ut erat ac magna ullamcorper hendrerit. " +
            "Cras pellentesque libero semper, gravida magna sed, luctus leo. Fusce lectus odio, laoreet" +
            "nec ullamcorper ut, molestie eu elit. Interdum et malesuada fames ac ante ipsum primis in faucibus." +
            "Aliquam lacinia sit amet elit ac consectetur. Donec cursus condimentum ligula, vitae volutpat" +
            "sem tristique eget. Nulla in consectetur massa. Vestibulum vitae lobortis ante. Nulla ullamcorper" +
            "pellentesque justo rhoncus accumsan. Mauris ornare eu odio non lacinia. Aliquam massa leo, rhoncus" +
            "ac iaculis eget, tempus et magna. Sed non consectetur elit. Sed vulputate, quam sed lacinia luctus," +
            "ipsum nibh fringilla purus, vitae posuere risus odio id massa. Cras sed venenatis lacus.");

        rootElement.AppendChild(mainHeader);
        rootElement.AppendChild(paragraphElement);

        // Save Tagged PDF Document
        document.Save(dataDir + "TaggedPdfDocument_out.pdf");
    }
}

.NET 8

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void CreateTaggedPdfDocument01()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();

    // Create PDF Document
    using var document = new Aspose.Pdf.Document();

    // Get Content for work with TaggedPdf
    Aspose.Pdf.Tagged.ITaggedContent taggedContent = document.TaggedContent;
    var rootElement = taggedContent.RootElement;

    // Set Title and Language for Document
    taggedContent.SetTitle("Tagged Pdf Document");
    taggedContent.SetLanguage("en-US");

    Aspose.Pdf.LogicalStructure.HeaderElement mainHeader = taggedContent.CreateHeaderElement();
    mainHeader.SetText("Main Header");

    Aspose.Pdf.LogicalStructure.ParagraphElement paragraphElement = taggedContent.CreateParagraphElement();
    paragraphElement.SetText("Lorem ipsum dolor sit amet, consectetur adipiscing elit. " +
        "Aenean nec lectus ac sem faucibus imperdiet. Sed ut erat ac magna ullamcorper hendrerit. " +
        "Cras pellentesque libero semper, gravida magna sed, luctus leo. Fusce lectus odio, laoreet" +
        "nec ullamcorper ut, molestie eu elit. Interdum et malesuada fames ac ante ipsum primis in faucibus." +
        "Aliquam lacinia sit amet elit ac consectetur. Donec cursus condimentum ligula, vitae volutpat" +
        "sem tristique eget. Nulla in consectetur massa. Vestibulum vitae lobortis ante. Nulla ullamcorper" +
        "pellentesque justo rhoncus accumsan. Mauris ornare eu odio non lacinia. Aliquam massa leo, rhoncus" +
        "ac iaculis eget, tempus et magna. Sed non consectetur elit. Sed vulputate, quam sed lacinia luctus," +
        "ipsum nibh fringilla purus, vitae posuere risus odio id massa. Cras sed venenatis lacus.");

    rootElement.AppendChild(mainHeader);
    rootElement.AppendChild(paragraphElement);

    // Save Tagged PDF Document
    document.Save(dataDir + "TaggedPdfDocument_out.pdf");
}

创建后，我们将得到以下文档：

创建带标签的 PDF 及嵌套元素（创建结构元素树）

在某些情况下，我们需要创建更复杂的结构，例如在段落中放置引号。 为了创建结构元素树，我们应该使用 AppendChild 方法。 以下代码片段展示了如何创建带标签 PDF 文档的结构元素树：

.NET Core 3.1

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void CreateTaggedPdfDocument02()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();

    // Create PDF Document
    using (var document = new Aspose.Pdf.Document())
    {
        // Get Content for work with TaggedPdf
        Aspose.Pdf.Tagged.ITaggedContent taggedContent = document.TaggedContent;
        var rootElement = taggedContent.RootElement;

        // Set Title and Language for Document
        taggedContent.SetTitle("Tagged Pdf Document");
        taggedContent.SetLanguage("en-US");

        Aspose.Pdf.LogicalStructure.HeaderElement header1 = taggedContent.CreateHeaderElement(1);
        header1.SetText("Header Level 1");

        Aspose.Pdf.LogicalStructure.ParagraphElement paragraphWithQuotes = taggedContent.CreateParagraphElement();
        paragraphWithQuotes.StructureTextState.Font = Aspose.Pdf.Text.FontRepository.FindFont("Calibri");
        paragraphWithQuotes.AdjustPosition(new Aspose.Pdf.Tagged.PositionSettings
            {
                Margin = new Aspose.Pdf.MarginInfo(10, 5, 10, 5)
            });

        Aspose.Pdf.LogicalStructure.SpanElement spanElement1 = taggedContent.CreateSpanElement();
        spanElement1.SetText("Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean nec lectus ac sem faucibus imperdiet. Sed ut erat ac magna ullamcorper hendrerit. Cras pellentesque libero semper, gravida magna sed, luctus leo. Fusce lectus odio, laoreet nec ullamcorper ut, molestie eu elit. Interdum et malesuada fames ac ante ipsum primis in faucibus. Aliquam lacinia sit amet elit ac consectetur. Donec cursus condimentum ligula, vitae volutpat sem tristique eget. Nulla in consectetur massa. Vestibulum vitae lobortis ante. Nulla ullamcorper pellentesque justo rhoncus accumsan. Mauris ornare eu odio non lacinia. Aliquam massa leo, rhoncus ac iaculis eget, tempus et magna. Sed non consectetur elit. ");

        Aspose.Pdf.LogicalStructure.QuoteElement quoteElement = taggedContent.CreateQuoteElement();
        quoteElement.SetText("Sed vulputate, quam sed lacinia luctus, ipsum nibh fringilla purus, vitae posuere risus odio id massa.");
        quoteElement.StructureTextState.FontStyle = Aspose.Pdf.Text.FontStyles.Bold | Aspose.Pdf.Text.FontStyles.Italic;
        Aspose.Pdf.LogicalStructure.SpanElement spanElement2 = taggedContent.CreateSpanElement();
        spanElement2.SetText(" Sed non consectetur elit.");

        paragraphWithQuotes.AppendChild(spanElement1);
        paragraphWithQuotes.AppendChild(quoteElement);
        paragraphWithQuotes.AppendChild(spanElement2);

        rootElement.AppendChild(header1);
        rootElement.AppendChild(paragraphWithQuotes);

        // Save Tagged PDF Document
        document.Save(dataDir + "TaggedPdfDocument_out.pdf");
    }
}

.NET 8

// For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
private static void CreateTaggedPdfDocument02()
{
    // The path to the documents directory
    var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();

    // Create PDF Document
    using var document = new Aspose.Pdf.Document();

    // Get Content for work with TaggedPdf
    Aspose.Pdf.Tagged.ITaggedContent taggedContent = document.TaggedContent;
    var rootElement = taggedContent.RootElement;

    // Set Title and Language for Document
    taggedContent.SetTitle("Tagged Pdf Document");
    taggedContent.SetLanguage("en-US");

    Aspose.Pdf.LogicalStructure.HeaderElement header1 = taggedContent.CreateHeaderElement(1);
    header1.SetText("Header Level 1");

    Aspose.Pdf.LogicalStructure.ParagraphElement paragraphWithQuotes = taggedContent.CreateParagraphElement();
    paragraphWithQuotes.StructureTextState.Font = Aspose.Pdf.Text.FontRepository.FindFont("Calibri");
    
    paragraphWithQuotes.AdjustPosition(new Aspose.Pdf.Tagged.PositionSettings
        {
            Margin = new Aspose.Pdf.MarginInfo(10, 5, 10, 5)
        });

    Aspose.Pdf.LogicalStructure.SpanElement spanElement1 = taggedContent.CreateSpanElement();
    spanElement1.SetText("Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean nec lectus ac sem faucibus imperdiet. Sed ut erat ac magna ullamcorper hendrerit. Cras pellentesque libero semper, gravida magna sed, luctus leo. Fusce lectus odio, laoreet nec ullamcorper ut, molestie eu elit. Interdum et malesuada fames ac ante ipsum primis in faucibus. Aliquam lacinia sit amet elit ac consectetur. Donec cursus condimentum ligula, vitae volutpat sem tristique eget. Nulla in consectetur massa. Vestibulum vitae lobortis ante. Nulla ullamcorper pellentesque justo rhoncus accumsan. Mauris ornare eu odio non lacinia. Aliquam massa leo, rhoncus ac iaculis eget, tempus et magna. Sed non consectetur elit. ");

    Aspose.Pdf.LogicalStructure.QuoteElement quoteElement = taggedContent.CreateQuoteElement();
    quoteElement.SetText("Sed vulputate, quam sed lacinia luctus, ipsum nibh fringilla purus, vitae posuere risus odio id massa.");
    quoteElement.StructureTextState.FontStyle = Aspose.Pdf.Text.FontStyles.Bold | Aspose.Pdf.Text.FontStyles.Italic;
    Aspose.Pdf.LogicalStructure.SpanElement spanElement2 = taggedContent.CreateSpanElement();
    spanElement2.SetText(" Sed non consectetur elit.");

    paragraphWithQuotes.AppendChild(spanElement1);
    paragraphWithQuotes.AppendChild(quoteElement);
    paragraphWithQuotes.AppendChild(spanElement2);

    rootElement.AppendChild(header1);
    rootElement.AppendChild(paragraphWithQuotes);

    // Save Tagged PDF Document
    document.Save(dataDir + "TaggedPdfDocument_out.pdf");
}

创建后，我们将得到以下文档：

样式文本结构

为了在带标签的 PDF 文档中样式化文本结构，Aspose.PDF 提供了 Font、FontSize、FontStyle 和 ForegroundColor 属性的 StructureTextState 类。以下代码片段展示了如何在带标签的 PDF 文档中样式化文本结构：

.NET Core 3.1

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

    // Create PDF Document
    using (var document = new Aspose.Pdf.Document())
    {
        // Get Content for work with TaggedPdf
        Aspose.Pdf.Tagged.ITaggedContent taggedContent = document.TaggedContent;

        // Set Title and Language for Document
        taggedContent.SetTitle("Tagged Pdf Document");
        taggedContent.SetLanguage("en-US");

        Aspose.Pdf.LogicalStructure.ParagraphElement p = taggedContent.CreateParagraphElement();
        taggedContent.RootElement.AppendChild(p);

        p.StructureTextState.FontSize = 18F;
        p.StructureTextState.ForegroundColor = Aspose.Pdf.Color.Red;
        p.StructureTextState.FontStyle = Aspose.Pdf.Text.FontStyles.Italic;

        p.SetText("Red italic text.");

        // Save Tagged PDF Document
        document.Save(dataDir + "StyleTextStructure_out.pdf");
    }
}

.NET 8

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

    // Create PDF Document
    using var document = new Aspose.Pdf.Document();

    // Get Content for work with TaggedPdf
    Aspose.Pdf.Tagged.ITaggedContent taggedContent = document.TaggedContent;

    // Set Title and Language for Document
    taggedContent.SetTitle("Tagged Pdf Document");
    taggedContent.SetLanguage("en-US");

    Aspose.Pdf.LogicalStructure.ParagraphElement p = taggedContent.CreateParagraphElement();
    taggedContent.RootElement.AppendChild(p);

    p.StructureTextState.FontSize = 18F;
    p.StructureTextState.ForegroundColor = Aspose.Pdf.Color.Red;
    p.StructureTextState.FontStyle = Aspose.Pdf.Text.FontStyles.Italic;

    p.SetText("Red italic text.");

    // Save Tagged PDF Document
    document.Save(dataDir + "StyleTextStructure_out.pdf");
}

说明结构元素

为了在带标签的 PDF 文档中说明结构元素，Aspose.PDF 提供了 IllustrationElement 类。以下代码片段展示了如何在带标签的 PDF 文档中说明结构元素：

.NET Core 3.1

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

    // Create PDF Document
    using (var document = new Aspose.Pdf.Document())
    {
        // Get Content for work with TaggedPdf
        Aspose.Pdf.Tagged.ITaggedContent taggedContent = document.TaggedContent;

        // Set Title and Language for Document
        taggedContent.SetTitle("Tagged Pdf Document");
        taggedContent.SetLanguage("en-US");

        Aspose.Pdf.LogicalStructure.IllustrationElement figure1 = taggedContent.CreateFigureElement();
        taggedContent.RootElement.AppendChild(figure1);
        figure1.AlternativeText = "Figure One";
        figure1.Title = "Image 1";
        figure1.SetTag("Fig1");
        figure1.SetImage(dataDir + "image.png");
        
        // Adjust position
        figure1.AdjustPosition(new Aspose.Pdf.Tagged.PositionSettings
        {
            Margin = new Aspose.Pdf.MarginInfo
            {
                Left = 50,
                Top = 20
            },
        });

        // Save Tagged PDF Document
        document.Save(dataDir + "IllustrationStructureElements_out.pdf");
    }
}

.NET 8

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

    // Create PDF Document
    using var document = new Aspose.Pdf.Document();

    // Get Content for work with TaggedPdf
    Aspose.Pdf.Tagged.ITaggedContent taggedContent = document.TaggedContent;

    // Set Title and Language for Document
    taggedContent.SetTitle("Tagged Pdf Document");
    taggedContent.SetLanguage("en-US");

    Aspose.Pdf.LogicalStructure.IllustrationElement figure1 = taggedContent.CreateFigureElement();
    taggedContent.RootElement.AppendChild(figure1);
    figure1.AlternativeText = "Figure One";
    figure1.Title = "Image 1";
    figure1.SetTag("Fig1");
    figure1.SetImage(dataDir + "image.png");
    
    // Adjust position
    figure1.AdjustPosition(new Aspose.Pdf.Tagged.PositionSettings
    {
        Margin = new Aspose.Pdf.MarginInfo
        {
            Left = 50,
            Top = 20
        },
    });

    // Save Tagged PDF Document
    document.Save(dataDir + "IllustrationStructureElements_out.pdf");
}

验证带标签的 PDF

Aspose.PDF for .NET 提供了验证 PDF/UA 带标签 PDF 文档的能力。PDF/UA 标准的验证支持：

• 检查 XObjects。
• 检查操作。
• 检查可选内容。
• 检查嵌入文件。
• 检查 Acroform 字段（验证自然语言、替代名称和数字签名）。
• 检查 XFA 表单字段。
• 检查安全设置。
• 检查导航。
• 检查注释。

以下代码片段展示了如何验证带标签的 PDF 文档。相应的问题将显示在 XML 日志报告中。

.NET Core 3.1

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

    // Open PDF document
    using (var document = new Aspose.Pdf.Document(dataDir + "StructureElements.pdf"))
    {
        bool isValid = document.Validate(dataDir + "StructureElements_log.xml", Aspose.Pdf.PdfFormat.PDF_UA_1);
    }
}

.NET 8

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

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

    bool isValid = document.Validate(dataDir + "StructureElements_log.xml", Aspose.Pdf.PdfFormat.PDF_UA_1);
}

调整文本结构的位置

以下代码片段展示了如何调整带标签 PDF 文档中文本结构的位置：

.NET Core 3.1

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

    // Create PDF Document
    using (var document = new Aspose.Pdf.Document())
    {
        // Get Content for work with TaggedPdf
        var taggedContent = document.TaggedContent;

        // Set Title and Language for Document
        taggedContent.SetTitle("Tagged Pdf Document");
        taggedContent.SetLanguage("en-US");

        // Create paragraph
        var p = taggedContent.CreateParagraphElement();
        taggedContent.RootElement.AppendChild(p);
        p.SetText("Text.");

        // Adjust position
        p.AdjustPosition(new Aspose.Pdf.Tagged.PositionSettings
        {
            HorizontalAlignment = Aspose.Pdf.HorizontalAlignment.None,
            Margin = new Aspose.Pdf.MarginInfo
            {
                Left = 300,
                Right = 0,
                Top = 20,
                Bottom = 0
            },
            VerticalAlignment = Aspose.Pdf.VerticalAlignment.None,
            IsFirstParagraphInColumn = false,
            IsKeptWithNext = false,
            IsInNewPage = false,
            IsInLineParagraph = false
        });

        // Save Tagged PDF Document
        document.Save(dataDir + "AdjustTextPosition_out.pdf");
    }
}

.NET 8

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

    // Create PDF Document
    using var document = new Aspose.Pdf.Document();
    
    // Get Content for work with TaggedPdf
    var taggedContent = document.TaggedContent;

    // Set Title and Language for Document
    taggedContent.SetTitle("Tagged Pdf Document");
    taggedContent.SetLanguage("en-US");

    // Create paragraph
    var p = taggedContent.CreateParagraphElement();
    taggedContent.RootElement.AppendChild(p);
    p.SetText("Text.");

    // Adjust position
    p.AdjustPosition(new Aspose.Pdf.Tagged.PositionSettings
    {
        HorizontalAlignment = Aspose.Pdf.HorizontalAlignment.None,
        Margin = new Aspose.Pdf.MarginInfo
        {
            Left = 300,
            Right = 0,
            Top = 20,
            Bottom = 0
        },
        VerticalAlignment = Aspose.Pdf.VerticalAlignment.None,
        IsFirstParagraphInColumn = false,
        IsKeptWithNext = false,
        IsInNewPage = false,
        IsInLineParagraph = false
    });

    // Save Tagged PDF Document
    document.Save(dataDir + "AdjustTextPosition_out.pdf");
}

使用 PDF/UA-1 转换自动创建带标签的 PDF

Aspose.PDF 在将文档转换为 PDF/UA-1 时启用基本逻辑结构标记的自动生成。用户可以手动改进此基本逻辑结构，提供有关文档内容的额外见解。

要生成逻辑文档结构，请创建 Aspose.Pdf.AutoTaggingSettings 类的实例，将其 AutoTaggingSettings.EnableAutoTagging 属性设置为 true，并将其分配给 PdfFormatConversionOptions.AutoTaggingSettings 属性。

如果文档已经具有逻辑结构标签，则启用自动标记将破坏现有的逻辑结构并生成一个新的结构。

.NET Core 3.1

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

    // Open PDF document
    using (Aspose.Pdf.Document document = new Aspose.Pdf.Document(dataDir + "BreakfastMenu.pdf"))
    {
        // Create conversion options
        Aspose.Pdf.PdfFormatConversionOptions options = new Aspose.Pdf.PdfFormatConversionOptions(dataDir + "ConvertToPdfUAWithAutomaticTagging.xml", PdfFormat.PDF_UA_1, ConvertErrorAction.Delete);

        // Create auto-tagging settings
        // Aspose.Pdf.AutoTaggingSettings.Default may be used to set the same settings as given below
        Aspose.Pdf.AutoTaggingSettings autoTaggingSettings = new Aspose.Pdf.AutoTaggingSettings();

        // Enable auto-tagging during the conversion process
        autoTaggingSettings.EnableAutoTagging = true;

        // Use the heading recognition strategy that's optimal for the given document structure
        autoTaggingSettings.HeadingRecognitionStrategy = Aspose.Pdf.HeadingRecognitionStrategy.Auto;

        // Assign auto-tagging settings to be used during the conversion process
        options.AutoTaggingSettings = autoTaggingSettings;

        // During the conversion, the document logical structure will be automatically created
        document.Convert(options);

        // Save PDF document
        document.Save(dataDir + "ConvertToPdfUAWithAutomaticTagging_out.pdf");
    }
}

.NET 8

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

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

    // Create conversion options
    Aspose.Pdf.PdfFormatConversionOptions options = new Aspose.Pdf.PdfFormatConversionOptions(dataDir + "ConvertToPdfUAWithAutomaticTagging.xml", PdfFormat.PDF_UA_1, ConvertErrorAction.Delete);

    // Create auto-tagging settings
    // Aspose.Pdf.AutoTaggingSettings.Default may be used to set the same settings as given below
    Aspose.Pdf.AutoTaggingSettings autoTaggingSettings = new Aspose.Pdf.AutoTaggingSettings
    {
        // Enable auto-tagging during the conversion process
        EnableAutoTagging = true,

        // Use the heading recognition strategy that's optimal for the given document structure
        HeadingRecognitionStrategy = Aspose.Pdf.HeadingRecognitionStrategy.Auto
    };

    // Assign auto-tagging settings to be used during the conversion process
    options.AutoTaggingSettings = autoTaggingSettings;

    // During the conversion, the document logical structure will be automatically created
    document.Convert(options);

    // Save PDF document
    document.Save(dataDir + "ConvertToPdfUAWithAutomaticTagging_out.pdf");
}

创建带表单字段的带标签 PDF

您可以在 PDF 文档中标记交互式表单字段，以确保它们包含在逻辑结构树中以便于访问（PDF/UA）。下面的代码片段演示了如何创建一个表单字段，将其注册到 AcroForm，并将其与结构树中的 /Form 结构元素关联。

.NET Core 3.1

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

    // Create PDF document
    using (var document = new Aspose.Pdf.Document())
    {
        document.Pages.Add();
        
        // Get Content for work with TaggedPdf
        Aspose.Pdf.Tagged.ITaggedContent taggedContent = document.TaggedContent;
        Aspose.Pdf.LogicalStructure.StructureElement rootElement = taggedContent.RootElement;

        // Create a visible signature form field (AcroForm)
        var signatureField = new Aspose.Pdf.Forms.SignatureField(document.Pages[1], new Aspose.Pdf.Rectangle(50, 50, 100, 100));
        signatureField.PartialName = "Signature1";
        signatureField.AlternateName = "signature 1";
        
        // Add the signature field to the document's AcroForm
        document.Form.Add(signatureField);

        // Create a /Form structure element in the tag tree
        Aspose.Pdf.LogicalStructure.FormElement form = taggedContent.CreateFormElement();
        form.AlternativeText = "form 1";
        
        // Link the /Form tag to the signature field via an /OBJR reference
        form.Tag(signatureField);
        
        // Add the /Form structure element to the document’s logical structure tree
        rootElement.AppendChild(form);

        // Save PDF document
        document.Save(dataDir + "CreatePdfWithTaggedFormField_out.pdf");
    }
}

.NET 8

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

    // Create PDF document
    using var document = new Aspose.Pdf.Document();
    
    document.Pages.Add();
    
    // Get Content for work with TaggedPdf
    Aspose.Pdf.Tagged.ITaggedContent taggedContent = document.TaggedContent;
    Aspose.Pdf.LogicalStructure.StructureElement rootElement = taggedContent.RootElement;

    // Create a visible signature form field (AcroForm)
    var signatureField = new Aspose.Pdf.Forms.SignatureField(document.Pages[1], new Aspose.Pdf.Rectangle(50, 50, 100, 100));
    signatureField.PartialName = "Signature1";
    signatureField.AlternateName = "signature 1";
    
    // Add the signature field to the document's AcroForm
    document.Form.Add(signatureField);

    // Create a /Form structure element in the tag tree
    Aspose.Pdf.LogicalStructure.FormElement form = taggedContent.CreateFormElement();
    form.AlternativeText = "form 1";
    
    // Link the /Form tag to the signature field via an /OBJR reference
    form.Tag(signatureField);
    
    // Add the /Form structure element to the document’s logical structure tree
    rootElement.AppendChild(form);

    // Save PDF document
    document.Save(dataDir + "CreatePdfWithTaggedFormField_out.pdf");
}

创建带有目录（TOC）页面的带标签 PDF

生成带有可访问目录（TOC）页面的带标签 PDF 文档。

.NET Core 3.1

    // For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
    private static void CreatePdfWithTOCpage()
    {
        // The path to the documents directory
        var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();
    
        // Create PDF document
        using (var doc = new Aspose.Pdf.Document())
        {
            // Get tagged content for the PDF structure
            Aspose.Pdf.Tagged.ITaggedContent content = doc.TaggedContent;
            Aspose.Pdf.LogicalStructure.StructureElement rootElement = content.RootElement;
            content.SetLanguage("en-US");
    
            // Add the table of contents (TOC) page
            Aspose.Pdf.Page tocPage = doc.Pages.Add();
            tocPage.TocInfo = new Aspose.Pdf.TocInfo();
    
            // Create a TOC structure element
            Aspose.Pdf.LogicalStructure.TOCElement tocElement = content.CreateTOCElement();
    
            // Add the TOC element to the document structure tree
            rootElement.AppendChild(tocElement);
    
            // Add a content page
            doc.Pages.Add();
    
            // Create a header element and set its text
            Aspose.Pdf.LogicalStructure.HeaderElement header = content.CreateHeaderElement(1);
            header.SetText("1. Header");
    
            // Add the header to the document structure
            rootElement.AppendChild(header);
    
            // Create a TOC item (TOCI) element
            Aspose.Pdf.LogicalStructure.TOCIElement toci = content.CreateTOCIElement();
    
            // Add the TOCI element to the TOC element
            tocElement.AppendChild(toci);
    
            // Add an entry to the TOC page and link it to the TOCI element
            header.AddEntryToTocPage(tocPage, toci);
    
            // Add a logical reference to the header within the TOCI element
            toci.AddRef(header);
    
            // Save PDF document
            doc.Save(dataDir + "CreatePdfWithTOCpage_out.pdf");
        }
    }

.NET 8

    // For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
    private static void CreatePdfWithTOCpage()
    {
        // The path to the documents directory
        var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();
    
        // Create PDF document
        using var doc = new Aspose.Pdf.Document();
        
        // Get tagged content for the PDF structure
        Aspose.Pdf.Tagged.ITaggedContent content = doc.TaggedContent;
        Aspose.Pdf.LogicalStructure.StructureElement rootElement = content.RootElement;
        content.SetLanguage("en-US");
    
        // Add the table of contents (TOC) page
        Aspose.Pdf.Page tocPage = doc.Pages.Add();
        tocPage.TocInfo = new Aspose.Pdf.TocInfo();
    
        // Create a TOC structure element
        Aspose.Pdf.LogicalStructure.TOCElement tocElement = content.CreateTOCElement();
    
        // Add the TOC element to the document structure tree
        rootElement.AppendChild(tocElement);
    
        // Add a content page
        doc.Pages.Add();
    
        // Create a header element and set its text
        Aspose.Pdf.LogicalStructure.HeaderElement header = content.CreateHeaderElement(1);
        header.SetText("1. Header");
    
        // Add the header to the document structure
        rootElement.AppendChild(header);
    
        // Create a TOC item (TOCI) element
        Aspose.Pdf.LogicalStructure.TOCIElement toci = content.CreateTOCIElement();
    
        // Add the TOCI element to the TOC element
        tocElement.AppendChild(toci);
    
        // Add an entry to the TOC page and link it to the TOCI element
        header.AddEntryToTocPage(tocPage, toci);
    
        // Add a logical reference to the header within the TOCI element
        toci.AddRef(header);
    
        // Save PDF document
        doc.Save(dataDir + "CreatePdfWithTOCpage_out.pdf");
    }

生成一个带有可访问目录页面的带标签 PDF，其中包含页面标题和嵌套子列表。

.NET Core 3.1

    // For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
    private static void CreatePdfWithTOCpageAdvanced()
    {
        // The path to the documents directory
        var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();
    
        // Create PDF document
        using (var doc = new Aspose.Pdf.Document())
        {
            // Get tagged content for the PDF structure
            Aspose.Pdf.Tagged.ITaggedContent content = doc.TaggedContent;
            Aspose.Pdf.LogicalStructure.StructureElement rootElement = content.RootElement;
            content.SetLanguage("en-US");
    
            // Add the table of contents (TOC) page
            Aspose.Pdf.Page tocPage = doc.Pages.Add();
            tocPage.TocInfo = new Aspose.Pdf.TocInfo();
            tocPage.TocInfo.Title = new Aspose.Pdf.Text.TextFragment("Table of Contents");
    
            // Create a TOC structure element
            Aspose.Pdf.LogicalStructure.TOCElement tocElement = content.CreateTOCElement();
    
            // Create a header element for the TOC page title
            Aspose.Pdf.LogicalStructure.HeaderElement headerForTOCpageTitle = content.CreateHeaderElement(1);
            tocElement.LinkTocPageTitleToHeaderElement(tocPage, headerForTOCpageTitle);
    
            // Add the TOC page title header and TOC element to the document structure tree
            rootElement.AppendChild(headerForTOCpageTitle);
            rootElement.AppendChild(tocElement);
    
            // Add a content page
            doc.Pages.Add();
    
            // Create a header element and set its text
            Aspose.Pdf.LogicalStructure.HeaderElement header = content.CreateHeaderElement(1);
            header.SetText("1. Header");
    
            // Add the header to the document structure
            rootElement.AppendChild(header);
    
            // Create a TOC item (TOCI) element
            Aspose.Pdf.LogicalStructure.TOCIElement toci = content.CreateTOCIElement();
    
            // Add the TOCI element to the TOC element
            tocElement.AppendChild(toci);
    
            // Add an entry to the TOC page and link it to the TOCI element
            header.AddEntryToTocPage(tocPage, toci);
    
            // Add a logical reference to the header within the TOCI element
            toci.AddRef(header);
    
            // Create a list element for TOCI subitems
            Aspose.Pdf.LogicalStructure.ListElement listElement = content.CreateListElement();
            for (var i = 1; i <= 3; i++)
            {
                // Create a list item (LI) element
                Aspose.Pdf.LogicalStructure.ListLIElement li = content.CreateListLIElement();
    
                // Add the list item to the list element
                listElement.AppendChild(li);
    
                // Create a sub-header element and set its properties
                Aspose.Pdf.LogicalStructure.HeaderElement subHeader = content.CreateHeaderElement(2);
                subHeader.StructureTextState.FontSize = 14;
                subHeader.Language = "en-US";
                subHeader.SetText($@"1.{i} subheader ");
    
                // Add an entry to the TOC page and link it to the LI element
                subHeader.AddEntryToTocPage(tocPage, li);
    
                // Add a logical reference to the subheader element
                li.AddRef(subHeader);
    
                // Create a paragraph element and set its text and language
                Aspose.Pdf.LogicalStructure.ParagraphElement p = content.CreateParagraphElement();
                p.SetText("Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.");
                p.Language = "en-US";
    
                // Add the sub-header and paragraph to the document structure
                rootElement.AppendChild(subHeader);
                rootElement.AppendChild(p);
            }
    
            // Add the list element as a child to the TOCI element
            toci.AppendChild(listElement);
    
            // --- Additional TOC header example ---
            // Create a second header element (see comments above for header 1)
            Aspose.Pdf.LogicalStructure.HeaderElement header2 = content.CreateHeaderElement(1);
            header2.SetText("2. Header");
            rootElement.AppendChild(header2);
    
            Aspose.Pdf.LogicalStructure.TOCIElement toci2 = content.CreateTOCIElement();
            tocElement.AppendChild(toci2);
    
            header2.AddEntryToTocPage(tocPage, toci2);
            toci2.AddRef(header2);
    
            // Save the PDF document
            doc.Save(dataDir + "CreatePdfWithTOCpageAdvanced_out.pdf");
        }
    }

.NET 8

    // For complete examples and data files, visit https://github.com/aspose-pdf/Aspose.PDF-for-.NET
    private static void CreatePdfWithTOCpageAdvanced()
    {
        // The path to the documents directory
        var dataDir = RunExamples.GetDataDir_AsposePdf_WorkingDocuments();
    
        // Create PDF document
        using var doc = new Aspose.Pdf.Document();
        
        // Get tagged content for the PDF structure
        Aspose.Pdf.Tagged.ITaggedContent content = doc.TaggedContent;
        Aspose.Pdf.LogicalStructure.StructureElement rootElement = content.RootElement;
        content.SetLanguage("en-US");
    
        // Add the table of contents (TOC) page
        Aspose.Pdf.Page tocPage = doc.Pages.Add();
        tocPage.TocInfo = new Aspose.Pdf.TocInfo();
        tocPage.TocInfo.Title = new Aspose.Pdf.Text.TextFragment("Table of Contents");
    
        // Create a TOC structure element
        Aspose.Pdf.LogicalStructure.TOCElement tocElement = content.CreateTOCElement();
    
        // Create a header element for the TOC page title
        Aspose.Pdf.LogicalStructure.HeaderElement headerForTOCpageTitle = content.CreateHeaderElement(1);
        tocElement.LinkTocPageTitleToHeaderElement(tocPage, headerForTOCpageTitle);
    
        // Add the TOC page title header and TOC element to the document structure tree
        rootElement.AppendChild(headerForTOCpageTitle);
        rootElement.AppendChild(tocElement);
    
        // Add a content page
        doc.Pages.Add();
    
        // Create a header element and set its text
        Aspose.Pdf.LogicalStructure.HeaderElement header = content.CreateHeaderElement(1);
        header.SetText("1. Header");
    
        // Add the header to the document structure
        rootElement.AppendChild(header);
    
        // Create a TOC item (TOCI) element
        Aspose.Pdf.LogicalStructure.TOCIElement toci = content.CreateTOCIElement();
    
        // Add the TOCI element to the TOC element
        tocElement.AppendChild(toci);
    
        // Add an entry to the TOC page and link it to the TOCI element
        header.AddEntryToTocPage(tocPage, toci);
    
        // Add a logical reference to the header within the TOCI element
        toci.AddRef(header);
    
        // Create a list element for TOCI subitems
        Aspose.Pdf.LogicalStructure.ListElement listElement = content.CreateListElement();
        for (var i = 1; i <= 3; i++)
        {
            // Create a list item (LI) element
            Aspose.Pdf.LogicalStructure.ListLIElement li = content.CreateListLIElement();
    
            // Add the list item to the list element
            listElement.AppendChild(li);
    
            // Create a sub-header element and set its properties
            Aspose.Pdf.LogicalStructure.HeaderElement subHeader = content.CreateHeaderElement(2);
            subHeader.StructureTextState.FontSize = 14;
            subHeader.Language = "en-US";
            subHeader.SetText($@"1.{i} subheader ");
    
            // Add an entry to the TOC page and link it to the LI element
            subHeader.AddEntryToTocPage(tocPage, li);
    
            // Add a logical reference to the subheader element
            li.AddRef(subHeader);
    
            // Create a paragraph element and set its text and language
            Aspose.Pdf.LogicalStructure.ParagraphElement p = content.CreateParagraphElement();
            p.SetText("Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.");
            p.Language = "en-US";
    
            // Add the sub-header and paragraph to the document structure
            rootElement.AppendChild(subHeader);
            rootElement.AppendChild(p);
        }
    
        // Add the list element as a child to the TOCI element
        toci.AppendChild(listElement);
    
        // --- Additional TOC header example ---
        // Create a second header element (see comments above for header 1)
        Aspose.Pdf.LogicalStructure.HeaderElement header2 = content.CreateHeaderElement(1);
        header2.SetText("2. Header");
        rootElement.AppendChild(header2);
    
        Aspose.Pdf.LogicalStructure.TOCIElement toci2 = content.CreateTOCIElement();
        tocElement.AppendChild(toci2);
    
        header2.AddEntryToTocPage(tocPage, toci2);
        toci2.AddRef(header2);
    
        // Save the PDF document
        doc.Save(dataDir + "CreatePdfWithTOCpageAdvanced_out.pdf");
    }