# Document Metadata

> Write title, author and keywords into PDFs from a Windows Forms TextControl, update an existing PDF, index PDFs with ServerTextControl and read raw metadata.

- **Product:** TX Text Control .NET for Windows Forms
- **Section:** Documentation
- **Kind:** Topic
- **Path:** TX Text Control .NET for Windows Forms > PDF Processing > Document Metadata
- **3679 words**
- **Web URL:** https://docs.textcontrol.com/tx-text-control-dotnet-winforms/pdf/metadata/
- **LLMs URL:** https://docs.textcontrol.com/tx-text-control-dotnet-winforms/pdf/metadata/llms.txt
- **LLMs-Full URL:** https://docs.textcontrol.com/tx-text-control-dotnet-winforms/pdf/metadata/llms-full.txt

---

Title, author, subject and keywords describe a PDF without opening it: PDF readers show them in the document properties, desktop search indexes them and archives sort by them. In TX Text Control .NET for Windows Forms, this metadata belongs to the document in the `TextControl`. It is loaded with a document, edited in code or by the user in the sidebar and written into every PDF the editor saves. The sections below show where each value lives, how to set it before saving, how users edit it, how to read it from many files and how to store properties of your own.

Setting document properties with `SaveSettings` for a first PDF is part of [Create a PDF](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/getting-started/pdf/create/llms-full.txt) in Getting Started, and reading them after loading is shown in [Loading Documents](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/document-processing/loading/#read-information-about-a-loaded-document).

### Where Metadata Lives

The metadata of a PDF are the document properties of TX Text Control: `DocumentTitle`, `Author`, `DocumentSubject`, `DocumentKeywords`, `CreatorApplication`, `CreationDate` and `UserDefinedDocumentProperties`. [TextControl.DocumentSettings](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/reference/txtextcontrol/textcontrol/documentsettings-property/llms-full.txt) holds the values of the document in the editor, [SaveSettings](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/reference/txtextcontrol/savesettings/llms-full.txt) overrides them for one save and [LoadSettings](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/reference/txtextcontrol/loadsettings/llms-full.txt) returns those that `Load` read. [Document Properties](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/document-editor/properties/#what-document-properties-are) explains the three objects and lists each property with its value when it's empty.

### Set the Metadata Before Saving

The following handler in *Form1.cs* gives the document in `textControl1` a title, an author and keywords, and saves it as PDF with the name of your application as its creator. *Form1.cs* needs `using System;` and `using TXTextControl;`:

```csharp
private void savePdfButton_Click(object sender, EventArgs e)
{
    DocumentSettings documentSettings = textControl1.DocumentSettings;

    // Stays with the document for every later save
    if (string.IsNullOrWhiteSpace(documentSettings.DocumentTitle))
    {
        documentSettings.DocumentTitle = "Invoice INV-2025-001";
    }

    documentSettings.Author = Environment.UserName;
    documentSettings.DocumentKeywords = new string[] { "invoice", "INV-2025-001", "Acme Corporation" };

    // Overrides the document settings for this file only
    SaveSettings saveSettings = new SaveSettings()
    {
        CreatorApplication = "Invoice Desk",
        LastModificationDate = DateTime.Now
    };

    textControl1.Save("invoice.pdf", StreamType.AdobePDF, saveSettings);
}
```

The code works as follows:

- [DocumentSettings](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/reference/txtextcontrol/documentsettings/llms-full.txt) holds the metadata of the current document. Values changed there are saved with this document from now on, in PDF and in other formats.
- The title is set only if the document has none, so a title the user entered or a loaded document brought along is kept.
- `SaveSettings` sets the creating application and the modification date for this file. Everything else comes from `DocumentSettings`.

Open *invoice.pdf* in a PDF reader and show its document properties. Adobe Acrobat lists the values on the **Description** tab:

![The Document Properties dialog box of Adobe Acrobat for a PDF created with TX Text Control, showing its title, author, subject and keywords, the creation and modification dates and TX Text Control as the application.](https://docs.textcontrol.com/assets/img/tx-text-control-dotnet-winforms/pdf-document-properties.6bed9dcb.webp)

### Let Users Edit the Properties in the Sidebar

The **DocumentSettings** panel of the [Sidebar](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/reference/txtextcontrol-windows-forms/sidebar/llms-full.txt) lets users edit the title, author, subject, keywords and custom properties of the document in the editor, and whatever they enter is saved with the next `Save`. [Let Users Edit the Properties](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/document-editor/properties/#let-users-edit-the-properties) shows the panel and how to display it, and [Let Users Manage Attachments in the Sidebar](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/pdf/attachments/#let-users-manage-attachments-in-the-sidebar) opens it from a button.

### Update the Metadata of an Existing PDF

To change the keywords of a PDF, load it, change what you need and save it again. The title, author and subject of the original document stay, because they come from `DocumentSettings`:

```csharp
private void updatePdfButton_Click(object sender, EventArgs e)
{
    textControl1.Load("invoice.pdf", StreamType.AdobePDF);

    // Filled from the loaded PDF
    DocumentSettings documentSettings = textControl1.DocumentSettings;
    MessageBox.Show($"Title: {documentSettings.DocumentTitle}\nCreated with: {documentSettings.CreatorApplication}");

    documentSettings.DocumentKeywords = new string[] { "invoice", "INV-2025-001", "paid" };

    textControl1.Save("invoice-paid.pdf", StreamType.AdobePDF,
        new SaveSettings() { LastModificationDate = DateTime.Now });
}
```

Without a new `CreatorApplication`, the saved PDF still names the application that created the original file. Loading rebuilds the pages of the PDF as an editable document, as [PDF Import and Its Limitations](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/pdf/import/llms-full.txt) explains, so the saved PDF is a new document with the old metadata.

### Build a Keyword Index of PDF Files

Reading the metadata of many files doesn't need the editor. A [ServerTextControl](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/reference/txtextcontrol/servertextcontrol/llms-full.txt), the TX Text Control without a user interface, loads them one after the other. The following handler reads the PDF files of the folder *Invoices* and writes an index as JSON. It needs `using System.Collections.Generic;`, `using System.IO;`, `using System.Linq;` and `using System.Text.Json;`:

```csharp
private void buildIndexButton_Click(object sender, EventArgs e)
{
    List<object> index = new List<object>();

    using (ServerTextControl tx = new ServerTextControl())
    {
        // Initialize the new instance before using it
        tx.Create();

        foreach (string file in Directory.GetFiles("Invoices", "*.pdf"))
        {
            // Text only: the metadata doesn't need the layout of the pages
            LoadSettings loadSettings = new LoadSettings()
            {
                PDFImportSettings = PDFImportSettings.GenerateLines
            };

            tx.Load(file, StreamType.AdobePDF, loadSettings);

            index.Add(new
            {
                File = Path.GetFileName(file),
                Title = loadSettings.DocumentTitle,
                Author = loadSettings.Author,
                Keywords = (loadSettings.DocumentKeywords ?? Array.Empty<string>()).Select(keyword => keyword.Trim()).ToArray(),
                Created = loadSettings.CreationDate == DateTime.MinValue ? (DateTime?)null : loadSettings.CreationDate
            });
        }
    }

    File.WriteAllText("index.json", JsonSerializer.Serialize(index, new JsonSerializerOptions { WriteIndented = true }));
}
```

`DocumentKeywords` is `null` when a PDF has no keywords, and a missing date is `DateTime.MinValue`; the index stores an empty array and `null` for them. The blog article [Enhancing PDF Searchability in Large Repositories by Adding and Reading Keywords Using C# .NET](https://www.textcontrol.com/blog/2025/06/24/enhancing-pdf-searchability-in-large-repositories-by-adding-and-reading-keywords-using-csharp-dotnet/) recommends consistent tags and 5 to 10 keywords per document.

### Store Custom Properties

Besides the standard metadata, a document can carry properties of your own, such as an invoice number, in a [UserDefinedPropertyDictionary](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/reference/txtextcontrol/userdefinedpropertydictionary/llms-full.txt). [Set the Properties in Code](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/document-editor/properties/#set-the-properties-in-code) shows how to add and change them, and [Which Formats Store the Properties](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/document-editor/properties/#which-formats-store-the-properties) lists the formats that save them.

### Give an Accessible PDF Its Title

PDF/UA, the standard for accessible PDF documents, requires a document title: without one, a PDF fails accessibility validation. Since version 34.0, TX Text Control writes the structure of an accessible PDF, as [Create an Accessible PDF (PDF/UA)](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/pdf/creation-conversion/#create-an-accessible-pdf-pdf-ua) describes, and the title comes from `DocumentSettings.DocumentTitle`. In a desktop application, the user can supply it: the following handler opens the sidebar panel in a sidebar named `sidebarLeft` instead of saving when the title is missing. It needs `using TXTextControl.Windows.Forms;`:

```csharp
private void saveAccessiblePdfButton_Click(object sender, EventArgs e)
{
    if (string.IsNullOrWhiteSpace(textControl1.DocumentSettings.DocumentTitle))
    {
        // Let the user enter the title first
        sidebarLeft.ContentLayout = Sidebar.SidebarContentLayout.DocumentSettings;
        sidebarLeft.IsShown = true;
        MessageBox.Show("Enter a title for the document, then save it again.");
        return;
    }

    textControl1.Save("invoice.pdf", StreamType.AdobePDF);
}
```

The blog article [Preflighting PDF/UA Documents with TX Text Control in .NET C#](https://www.textcontrol.com/blog/2025/12/29/preflighting-pdf-ua-documents-with-tx-text-control-dotnet-csharp/) checks the title together with the descriptive texts of images and tables before a document is saved.

### Read the Raw Metadata of a PDF

With [PDFImportSettings](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/reference/txtextcontrol/pdfimportsettings/enumeration/llms-full.txt) `LoadEmbeddedData`, `Load` also provides the metadata of a PDF as it is stored in the file, in [LoadSettings.EmbeddedData](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/reference/txtextcontrol/loadsettings/embeddeddata-property/llms-full.txt). The dictionary's keys are values of [EmbeddedDataFormat](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/reference/txtextcontrol/embeddeddataformat/enumeration/llms-full.txt), and `MetaData` returns the metadata:

```csharp
private void showRawMetadataButton_Click(object sender, EventArgs e)
{
    LoadSettings loadSettings = new LoadSettings()
    {
        PDFImportSettings = PDFImportSettings.GenerateTextFrames | PDFImportSettings.LoadEmbeddedData
    };

    textControl1.Load("invoice.pdf", StreamType.AdobePDF, loadSettings);

    if (loadSettings.EmbeddedData != null &&
        loadSettings.EmbeddedData.TryGetValue(EmbeddedDataFormat.MetaData, out object metaData))
    {
        MessageBox.Show(metaData.ToString());
    }
}
```

`GenerateTextFrames` is the default import of a PDF, so the document looks the same in the editor as without the additional flag. The dictionary is filled only when `LoadEmbeddedData` is set, and it contains the formats the PDF provides; `TextCoordinates` is used in [Text Extraction](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/pdf/text-extraction/llms-full.txt).

### Next Steps

- [Attachments](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/pdf/attachments/llms-full.txt): embed files with their own metadata.
- [PDF/A](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/pdf/pdf-a/llms-full.txt): archive documents together with their metadata.
- [Sidebar and Panels](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/document-editor/ribbon-ui/sidebar/llms-full.txt): add the sidebar with the DocumentSettings panel.
- [Loading Documents](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/document-processing/loading/llms-full.txt): read the properties of any loaded document.

---

## Nearby

- **Previous:** [Text Extraction](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/pdf/text-extraction/llms-full.txt)
- **Next:** [Passwords and Access Permissions](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/pdf/passwords/llms-full.txt)