How do you set an image value on a PDF form image field?

An ImageFormField is a click-to-select placeholder, so the image value is supplied by the end user inside an interactive PDF viewer such as Adobe Acrobat at form-fill time. The ImageFormField class itself does not expose a byte array, Stream, file path, or AnyBitmap property for the image content; it carries only the field name, page index, placement geometry, and form flags. To programmatically place an image onto a PDF from C# code, use ImageStamper or the AnyBitmap-based stamping API instead of a form field, since stampers flatten the image into the page content and produce a non-interactive overlay.

Does SetDefaultFont work on ImageFormField?

No. The SetDefaultFont(string FontName, int FontSize, Color FontColor) method is declared on ImageFormField because it is part of the shared form-field surface, but calling it throws NotImplementedException with the condition 'Image form fields do not support setting of default font'. Font configuration is meaningful only for text-bearing field types such as TextFormField and ComboboxFormField. Skip SetDefaultFont when working with image fields and rely on the field's placement properties for visual control.

Why does the image field not appear when opening the PDF in a web browser?

Web-browser PDF viewers generally do not render the interactive image-upload widget that the PDF specification defines for image form fields. The widget will appear and be functional in Adobe Acrobat and other full-featured PDF viewers that support the image-field type. To test an ImageFormField after construction, open the saved PDF in Adobe Acrobat and confirm the placeholder region presents the file-selection dialog when clicked.

Class ImageFormField

Q: Where is ImageFormField located in the IronPDF object model?

ImageFormField is in the IronSoftware.Forms namespace, shipped in IronPdf.dll. It derives from System.Object and implements IFormField, IFormFieldObject, IFormFieldAnnotationObject, and IPdfDocumentObject. It is one of the concrete form-field classes a developer attaches to a document through pdf.Form.Add.

Form field which prompts for an image when clicked

Inheritance

System.Object

ImageFormField

Implements

IFormField

IFormFieldObject

IFormFieldAnnotationObject

IPdfDocumentObject

IronSoftware.Abstractions.Pdf.IPdfDocumentObject

IronSoftware.Abstractions.IDocumentObject

Namespace: IronSoftware.Forms

Assembly: IronPdf.dll

Syntax

public class ImageFormField : Object, IFormField, IFormFieldObject, IFormFieldAnnotationObject, IPdfDocumentObject, IPdfDocumentObject, IDocumentObject

Use ImageFormField when a PDF form needs a click-to-select image placeholder: a fillable region that a viewer prompts the end user to populate with a photograph, scan, or signature image at form-fill time. The class describes the field's name, page placement, geometry, and PDF form metadata; the image content itself is supplied by the user inside a PDF viewer that supports interactive forms, such as Adobe Acrobat.

ImageFormField is the right primitive for ID photo upload, signature capture, stamp insertion, headshot fields on application templates, and any workflow where the document author defines a placeholder region but the final image arrives from the form filler rather than from server-side code. The class encapsulates one image field as a reusable configuration object that is constructed once with the placement parameters and then attached to a PdfDocument for the write. Common scenarios include onboarding paperwork, KYC application forms, and printable templates that ship empty and are completed inside Acrobat.

Construct an ImageFormField with the single six-parameter constructor (string name, uint page_index, double x, double y, double width, double height). The name becomes the field's Name and round-trips through FullName for nested-form access. Placement is fixed by the X, Y, Width, and Height properties in PDF user-space points, and the field is bound to a specific page through PageIndex. Read-side identity is exposed through FormType and the strongly-typed Type (a PdfFormFieldType), and the standard form-field flags ride on FormFlags (typed as PdfFormFieldFlags) and the boolean ReadOnly. Once configured, attach the field to a document with pdf.Form.Add(imageField) on the FormFieldCollection returned by PdfDocument.Form. Constructing an image placeholder and attaching it has a worked example in the image-forms section of the create PDF forms how-to.

using IronPdf;
using IronSoftware.Forms;

ChromePdfRenderer renderer = new ChromePdfRenderer();
PdfDocument pdf = renderer.RenderHtmlAsPdf("<h2>Employment Application</h2>");

// Construct the image placeholder: name, page index, then X/Y/Width/Height
// in PDF user-space points from the lower-left corner of the page.
ImageFormField photoField = new ImageFormField(
    name: "ApplicantPhoto",
    page_index: 0,
    x: 400,
    y: 600,
    width: 150,
    height: 200);

// pdf.Form is a FormFieldCollection; Add accepts any IFormField.
pdf.Form.Add(photoField);

// Later, locate the field for further edits or removal.
// FindFormField returns IFormField; cast back to ImageFormField for
// type-specific access:
//   var found = pdf.Form.FindFormField("ApplicantPhoto") as ImageFormField;
//   pdf.Form.Remove(found);

pdf.SaveAs("application.pdf");

The output PDF must be opened in a viewer that supports interactive image forms; web-browser PDF viewers will display the document but not the image-upload widget. The full authoring surface for text inputs, checkboxes, radio groups, comboboxes, and signature fields sits alongside image fields in the create PDF forms how-to. To locate, reposition, or remove a field after the document is built, turn to the edit PDF forms how-to.

Constructors

ImageFormField(String, UInt32, Double, Double, Double, Double)

Create a new image field with the specified parameters

Declaration

public ImageFormField(string name, uint page_index, double x, double y, double width, double height)

Parameters

Type	Name	Description
System.String	name	Form name
System.UInt32	page_index	Form page index
System.Double	x	Form x-coordinate
System.Double	y	Form y-coordinate
System.Double	width	Form width
System.Double	height	Form height

Properties

Annotations

Form field annotations

Declaration

public List<IFormFieldAnnotation> Annotations { get; protected set; }

Property Value

Type	Description
System.Collections.Generic.List<IFormFieldAnnotation>

Choices

Selection choices

Declaration

public List<string> Choices { get; protected set; }

Property Value

Type	Description
System.Collections.Generic.List<System.String>

Client

Pdf client

Declaration

public IPdfClient Client { get; set; }

Property Value

Type	Description
IronSoftware.Pdfium.IPdfClient

DefaultAppearance

Default appearance string

Declaration

public string DefaultAppearance { get; set; }

Property Value

Type	Description
System.String

DocumentId

Declaration

public IDocumentId DocumentId { get; set; }

Property Value

Type	Description
IronSoftware.Abstractions.Pdf.IDocumentId

FormFlags

Form field flags

Declaration

public PdfFormFieldFlags FormFlags { get; set; }

Property Value

Type	Description
PdfFormFieldFlags

FormType

Form type

Declaration

public string FormType { get; }

Property Value

Type	Description
System.String

FullName

Fully qualified name

Declaration

public string FullName { get; protected set; }

Property Value

Type	Description
System.String

Height

Annotation height

Declaration

public double Height { get; set; }

Property Value

Type	Description
System.Double

MaxLength

Maximum number of characters which can be specified in the value

Declaration

public int MaxLength { get; set; }

Property Value

Type	Description
System.Int32

Name

Partial name

Declaration

public string Name { get; set; }

Property Value

Type	Description
System.String

ObjNum

Declaration

public uint ObjNum { get; set; }

Property Value

Type	Description
System.UInt32

ObjType

Object type

Declaration

public string ObjType { get; }

Property Value

Type	Description
System.String

PageIndex

Declaration

public uint PageIndex { get; set; }

Property Value

Type	Description
System.UInt32

ReadOnly

True if read-only

Declaration

public bool ReadOnly { get; set; }

Property Value

Type	Description
System.Boolean

RichText

Form value using rich text

Declaration

public string RichText { get; set; }

Property Value

Type	Description
System.String

Type

Pdf form field type

Declaration

public PdfFormFieldType Type { get; }

Property Value

Type	Description
PdfFormFieldType

Value

Form value

Declaration

public string Value { get; set; }

Property Value

Type	Description
System.String

Width

Annotation width

Declaration

public double Width { get; set; }

Property Value

Type	Description
System.Double

X

Annotation X position

Declaration

public double X { get; set; }

Property Value

Type	Description
System.Double

Y

Annotation y position

Declaration

public double Y { get; set; }

Property Value

Type	Description
System.Double

Methods

SetDefaultFont(String, Int32, Color)

NOT SUPPORTED

Declaration

public void SetDefaultFont(string FontName, int FontSize, Color FontColor)

Parameters

Type	Name	Description
System.String	FontName	n/a
System.Int32	FontSize	n/a
System.Drawing.Color	FontColor	n/a

Exceptions

Type	Condition
System.NotImplementedException	Image form fields do not support setting of default font

Implements

IFormField

IFormFieldObject

IFormFieldAnnotationObject

IPdfDocumentObject

IronSoftware.Abstractions.Pdf.IPdfDocumentObject

IronSoftware.Abstractions.IDocumentObject