PDFCheckBox · PDF-LIB

Represents a check box field of a PDFForm.

PDFCheckBox fields are interactive boxes that users can click with their mouse. This type of PDFField has two states: on and off. The purpose of a check box is to enable users to select from one or more options, where each option is represented by a single check box. Check boxes are typically square in shape and display a check mark when they are in the on state.

Hierarchy

PDFField

↳ PDFCheckBox

Index

Properties

Methods

Properties

acroField

• acroField: PDFAcroCheckBox

Overrides PDFField.acroField

Defined in api/form/PDFCheckBox.ts:49

The low-level PDFAcroCheckBox wrapped by this check box.

doc

• doc: PDFDocument

Inherited from PDFField.doc

Defined in api/form/PDFField.ts:92

The document to which this field belongs.

ref

• ref: PDFRef

Inherited from PDFField.ref

Defined in api/form/PDFField.ts:89

The unique reference assigned to this field within the document.

Methods

addToPage

▸ addToPage(page: PDFPage, options?: FieldAppearanceOptions): void

Defined in api/form/PDFCheckBox.ts:150

Show this check box on the specified page. For example:

const helvetica = await pdfDoc.embedFont(StandardFonts.Helvetica)
const page = pdfDoc.addPage()

const form = pdfDoc.getForm()
const checkBox = form.createCheckBox('some.checkBox.field')

checkBox.addToPage(page, {
  x: 50,
  y: 75,
  width: 25,
  height: 25,
  textColor: rgb(1, 0, 0),
  backgroundColor: rgb(0, 1, 0),
  borderColor: rgb(0, 0, 1),
  borderWidth: 2,
  rotate: degrees(90),
})

This will create a new widget for this check box field.

Parameters:

Name	Type	Description
`page`	PDFPage	The page to which this check box widget should be added.
`options?`	FieldAppearanceOptions	The options to be used when adding this check box widget.

Returns: void

check

▸ check(): void

Defined in api/form/PDFCheckBox.ts:84

Mark this check box. This operation is analogous to a human user clicking a check box to fill it in a PDF reader. This method will update the underlying state of the check box field to indicate it has been selected. PDF libraries and readers will be able to extract this value from the saved document and determine that it was selected.

For example:

const checkBox = form.getCheckBox('some.checkBox.field')
checkBox.check()

This method will mark this check box as dirty, causing its appearance streams to be updated when either PDFDocument.save or PDFForm.updateFieldAppearances is called. The updated appearance streams will display a check mark inside the widgets of this check box field.

Returns: void

defaultUpdateAppearances

▸ defaultUpdateAppearances(): void

Overrides void

Defined in api/form/PDFCheckBox.ts:219

Update the appearance streams for each of this check box's widgets using the default appearance provider for check boxes. For example:

const checkBox = form.getCheckBox('some.checkBox.field')
checkBox.defaultUpdateAppearances()

Returns: void

disableExporting

▸ disableExporting(): void

Inherited from PDFField.disableExporting

Defined in api/form/PDFField.ts:247

Indicate that this field's value should not be exported when the form is submitted in a PDF reader. For example:

const field = form.getField('some.field')
field.disableExporting()

Returns: void

disableReadOnly

▸ disableReadOnly(): void

Inherited from PDFField.disableReadOnly

Defined in api/form/PDFField.ts:170

Allow users to interact with this field and change its value in PDF readers via mouse and keyboard input. For example:

const field = form.getField('some.field')
field.disableReadOnly()

Returns: void

disableRequired

▸ disableRequired(): void

Inherited from PDFField.disableRequired

Defined in api/form/PDFField.ts:208

Do not require this field to have a value when the form is submitted. For example:

const field = form.getField('some.field')
field.disableRequired()

Returns: void

enableExporting

▸ enableExporting(): void

Inherited from PDFField.enableExporting

Defined in api/form/PDFField.ts:235

Indicate that this field's value should be exported when the form is submitted in a PDF reader. For example:

const field = form.getField('some.field')
field.enableExporting()

Returns: void

enableReadOnly

▸ enableReadOnly(): void

Inherited from PDFField.enableReadOnly

Defined in api/form/PDFField.ts:158

Prevent PDF readers from allowing users to interact with this field or change its value. The field will not respond to mouse or keyboard input. For example:

const field = form.getField('some.field')
field.enableReadOnly()

Useful for fields whose values are computed, imported from a database, or prefilled by software before being displayed to the user.

Returns: void

enableRequired

▸ enableRequired(): void

Inherited from PDFField.enableRequired

Defined in api/form/PDFField.ts:196

Require this field to have a value when the form is submitted. For example:

const field = form.getField('some.field')
field.enableRequired()

Returns: void

getName

▸ getName(): string

Inherited from PDFField.getName

Defined in api/form/PDFField.ts:128

Get the fully qualified name of this field. For example:

const fields = form.getFields()
fields.forEach(field => {
  const name = field.getName()
  console.log('Field name:', name)
})

Note that PDF fields are structured as a tree. Each field is the descendent of a series of ancestor nodes all the way up to the form node, which is always the root of the tree. Each node in the tree (except for the form node) has a partial name. Partial names can be composed of any unicode characters except a period (.). The fully qualified name of a field is composed of the partial names of all its ancestors joined with periods. This means that splitting the fully qualified name on periods and taking the last element of the resulting array will give you the partial name of a specific field.

Returns: string

The fully qualified name of this field.

isChecked

▸ isChecked(): boolean

Defined in api/form/PDFCheckBox.ts:120

Returns true if this check box is selected (either by a human user via a PDF reader, or else programmatically via software). For example:

const checkBox = form.getCheckBox('some.checkBox.field')
if (checkBox.isChecked()) console.log('check box is selected')

Returns: boolean

Whether or not this check box is selected.

isExported

▸ isExported(): boolean

Inherited from PDFField.isExported

Defined in api/form/PDFField.ts:223

Returns true if this field's value should be exported when the form is submitted. See PDFField.enableExporting and PDFField.disableExporting. For example:

const field = form.getField('some.field')
if (field.isExported()) console.log('Exporting is enabled')

Returns: boolean

Whether or not this field's value should be exported.

isReadOnly

▸ isReadOnly(): boolean

Inherited from PDFField.isReadOnly

Defined in api/form/PDFField.ts:143

Returns true if this field is read only. This means that PDF readers will not allow users to interact with the field or change its value. See PDFField.enableReadOnly and PDFField.disableReadOnly. For example:

const field = form.getField('some.field')
if (field.isReadOnly()) console.log('Read only is enabled')

Returns: boolean

Whether or not this is a read only field.

isRequired

▸ isRequired(): boolean

Inherited from PDFField.isRequired

Defined in api/form/PDFField.ts:184

Returns true if this field must have a value when the form is submitted. See PDFField.enableRequired and PDFField.disableRequired. For example:

const field = form.getField('some.field')
if (field.isRequired()) console.log('Field is required')

Returns: boolean

Whether or not this field is required.

needsAppearancesUpdate

▸ needsAppearancesUpdate(): boolean

Overrides void

Defined in api/form/PDFCheckBox.ts:197

Returns true if any of this check box's widgets do not have an appearance stream for its current state. For example:

const checkBox = form.getCheckBox('some.checkBox.field')
if (checkBox.needsAppearancesUpdate()) console.log('Needs update')

Returns: boolean

Whether or not this check box needs an appearance update.

uncheck

▸ uncheck(): void

Defined in api/form/PDFCheckBox.ts:106

Clears this check box. This operation is analogous to a human user clicking a check box to unmark it in a PDF reader. This method will update the underlying state of the check box field to indicate it has been deselected. PDF libraries and readers will be able to extract this value from the saved document and determine that it was not selected.

For example:

const checkBox = form.getCheckBox('some.checkBox.field')
checkBox.uncheck()

This method will mark this check box as dirty. See PDFCheckBox.check for more details about what this means.

Returns: void

updateAppearances

▸ updateAppearances(provider?: AppearanceProviderFor‹PDFCheckBox›): void

Defined in api/form/PDFCheckBox.ts:240

Update the appearance streams for each of this check box's widgets using the given appearance provider. If no provider is passed, the default appearance provider for check boxs will be used. For example:

const checkBox = form.getCheckBox('some.checkBox.field')
checkBox.updateAppearances((field, widget) => {
  ...
  return {
    normal: { on: drawCheckBox(...), off: drawCheckBox(...) },
    down: { on: drawCheckBox(...), off: drawCheckBox(...) },
  }
})

Parameters:

Name	Type	Description
`provider?`	AppearanceProviderFor‹PDFCheckBox›	Optionally, the appearance provider to be used for generating the contents of the appearance streams.

Returns: void

`Static` of

▸ of(acroCheckBox: PDFAcroCheckBox, ref: PDFRef, doc: PDFDocument): PDFCheckBox‹›

Defined in api/form/PDFCheckBox.ts:45

NOTE: You probably don't want to call this method directly. Instead, consider using the PDFForm.getCheckBox method, which will create an instance of PDFCheckBox for you.

Create an instance of PDFCheckBox from an existing acroCheckBox and ref

Parameters:

Name	Type	Description
`acroCheckBox`	PDFAcroCheckBox	The underlying `PDFAcroCheckBox` for this check box.
`ref`	PDFRef	The unique reference for this check box.
`doc`	PDFDocument	The document to which this check box will belong.

Returns: PDFCheckBox‹›

Hierarchy

Index

Properties

Methods

Properties

acroField

doc

ref

Methods

addToPage

check

defaultUpdateAppearances

disableExporting

disableReadOnly

disableRequired

enableExporting

enableReadOnly

enableRequired

getName

isChecked

isExported

isReadOnly

isRequired

needsAppearancesUpdate

uncheck

updateAppearances

Static of

`Static` of