### Install PdfPig via NuGet

Source: https://uglytoad.github.io/PdfPig

Use the Package Manager Console to install the PdfPig library.

```powershell
> Install-Package PdfPig
```

--------------------------------

### Accessing PDF Document Metadata and Forms

Source: https://uglytoad.github.io/PdfPig

Demonstrates opening a PDF file and retrieving information such as page count, form fields, XMP metadata, bookmarks, and embedded files.

```csharp
using System;
using System.Collections.Generic;
using System.Xml.Linq;
using UglyToad.PdfPig;
using UglyToad.PdfPig.AcroForms;
using UglyToad.PdfPig.AcroForms.Fields;
using UglyToad.PdfPig.Content;
using UglyToad.PdfPig.Outline;

public static class Program
{
    public static void Main()
    {
        using (PdfDocument document = PdfDocument.Open(@"C:\temp\file.pdf"))
        {
            Console.WriteLine($"Document has {document.NumberOfPages} pages.");

            if (document.TryGetForm(out AcroForm form))
            {
                foreach (AcroFieldBase field in form.GetFieldsForPage(1))
                {
                    switch (field)
                    {
                        case AcroCheckboxField cb:
                            if (cb.IsChecked)
                            {
                                Console.WriteLine($"Checkbox was checked: {cb.Information.MappingName}.");
                            }
                            break;
                    }
                }
            }

            if (document.TryGetXmpMetadata(out XmpMetadata metadata))
            {
                XDocument xmp = metadata.GetXDocument();
            }
            
            if (document.TryGetBookmarks(out Bookmarks bookmarks))
            {
                Console.WriteLine($"Document contained bookmarks with {bookmarks.Roots.Count} root nodes.");
            }

            Console.WriteLine($"Document uses version {document.Version} of the PDF specification.");

            if (document.Advanced.TryGetEmbeddedFiles(out IReadOnlyList<EmbeddedFile> embeddedFiles))
            {
                Console.WriteLine($"Document contains {embeddedFiles.Count} embedded files.");
            }
        }
    }
}
```

--------------------------------

### Create a PDF document with standard fonts

Source: https://uglytoad.github.io/PdfPig

Initializes a new PDF document, adds standard Helvetica fonts, writes text to an A4 page, and saves the result to a file.

```csharp
using System.IO;
using UglyToad.PdfPig.Content;
using UglyToad.PdfPig.Core;
using UglyToad.PdfPig.Fonts.Standard14Fonts;
using UglyToad.PdfPig.Writer;

public static class Program
{
    public static void Main()
    {
        PdfDocumentBuilder builder = new PdfDocumentBuilder();

        PdfDocumentBuilder.AddedFont helvetica = builder.AddStandard14Font(Standard14Font.Helvetica);
        PdfDocumentBuilder.AddedFont helveticaBold = builder.AddStandard14Font(Standard14Font.HelveticaBold);

        PdfPageBuilder page = builder.AddPage(PageSize.A4);

        PdfPoint closeToTop = new PdfPoint(15, page.PageSize.Top - 25);

        page.AddText("My first PDF document!", 12, closeToTop, helvetica);

        page.AddText("Hello World!", 10, closeToTop.Translate(0, -15), helveticaBold);

        File.WriteAllBytes(@"C:\temp\file.pdf", builder.Build());
    }
}
```

--------------------------------

### Open Password Protected PDF

Source: https://uglytoad.github.io/PdfPig

Provide a list of passwords via ParsingOptions to open encrypted PDF files and access document metadata.

```csharp
ParsingOptions parsingOptions = new ParsingOptions
{
    Passwords = new List<string> {"a password", "password123"}
};

using (PdfDocument document = PdfDocument.Open(@"C:\path\to\pdffile\file.pdf", parsingOptions))
{
    // Get the title from the document metadata.
    Console.WriteLine(document.Information.Title);
            
    foreach (Page page in document.GetPages())
    {
        IReadOnlyList<Letter> letters = page.Letters;
        Console.WriteLine(letters.Count);
    }
}
```

--------------------------------

### Read PDF Content

Source: https://uglytoad.github.io/PdfPig

Open a PDF document to access its pages, letters, words, and images.

```csharp
using System.Collections.Generic;
using System.Linq;
using UglyToad.PdfPig;
using UglyToad.PdfPig.Content;

public static class Program
{
    public static void Main()
    {
        using (PdfDocument document = PdfDocument.Open(@"C:\path\to\pdffile\file.pdf"))
        {
            foreach (Page page in document.GetPages())
            {
                IReadOnlyList<Letter> letters = page.Letters;
                string example = string.Join(string.Empty, letters.Select(x => x.Value));

                IEnumerable<Word> words = page.GetWords();

                IEnumerable<IPdfImage> images = page.GetImages();
            }
        }
    }
}
```

--------------------------------

### Register a TrueType font

Source: https://uglytoad.github.io/PdfPig

Registers a custom TrueType font from a file path to support non-ASCII text in the PDF document.

```csharp
PdfDocumentBuilder builder = new PdfDocumentBuilder();

// You must provide a valid path to a .ttf file.
byte[] robotoBytes = File.ReadAllBytes(@"C:\fonts\roboto.ttf");
PdfDocumentBuilder.AddedFont roboto = builder.AddTrueTypeFont(robotoBytes);
```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.