Class PdfAttachment

Represents a file attachment embedded within a PDF document. Provides access to attachment metadata and binary data for extraction or modification.

PDF attachments are complete files stored within the PDF container. They appear as paperclip icons in PDF readers and can contain any file type (spreadsheets, images, documents, etc.).

Example - Extract attachment to disk:

var pdf = PdfDocument.FromFile("invoice_with_receipt.pdf");
foreach (var attachment in pdf.Attachments)
{
    Console.WriteLine($"Found: {attachment.Name} at index {attachment.Index}");
    File.WriteAllBytes(attachment.Name, attachment.Data);
}

Inheritance
System.Object
PdfClientAccessor
PdfAttachment
Namespace: IronPdf
Assembly: IronPdf.dll
Syntax
public class PdfAttachment : PdfClientAccessor
Remarks

Common Use Cases:

Related Resources:

Properties

Data

Gets or sets the raw binary data of the attachment. Read to extract, write to replace content while preserving the filename.

Example - Extract and modify:

// Extract attachment data:
byte[] data = attachment.Data;
File.WriteAllBytes($"extracted_{attachment.Name}", data);

// Replace attachment content:
attachment.Data = File.ReadAllBytes("updated_receipt.pdf");
pdf.SaveAs("invoice_updated.pdf");

Declaration
public byte[] Data { get; set; }
Property Value
Type Description
System.Byte[]

The complete binary content of the attached file.
Remarks

Reading this property retrieves data from the PDF. For large attachments, consider caching the result if accessed multiple times.

Index

Gets the zero-based index of this attachment within the PDF document. Index may change if attachments are added or removed (alphabetically sorted).

Declaration
public int Index { get; }
Property Value
Type Description
System.Int32

Zero-based position in the attachment collection.

Name

Gets the filename of this attachment as stored in the PDF document. Typically includes file extension (e.g., "receipt.pdf", "data.xlsx").

Use this name when saving extracted attachments to preserve original filenames.

Declaration
public string Name { get; }
Property Value
Type Description
System.String

The attachment filename including extension.

See Also