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pdf-lib › PDFTextField Represents a text field of a PDFForm. PDFTextField fields are boxes that display text entered by the user. The purpose of a text field is to enable users to enter text or view text values in the document prefilled by software. Users can click on a text field and input text via their keyboard. Some text fields allow multiple lines of text to be entered (see ). Hierarchy Index Properties Methods Properties acroField• acroField: PDFAcroText Overrides PDFField. Defined in The low-level PDFAcroText wrapped by this text field. doc• doc: PDFDocument Inherited from PDFField. Defined in The document to which this field belongs. ref• ref: PDFRef Inherited from PDFField. Defined in The unique reference assigned to this field within the document. Methods addToPage▸ addToPage(page: PDFPage, options?: FieldAppearanceOptions): void Defined in Show this text field on the specified page. For example: const ubuntuFont = await pdfDoc.embedFont(ubuntuFontBytes) const page = pdfDoc.addPage() const form = pdfDoc.getForm() const textField = form.createTextField('best.gundam') textField.setText('Exia') textField.addToPage(page, { x: 50, y: 75, width: 200, height: 100, textColor: rgb(1, 0, 0), backgroundColor: rgb(0, 1, 0), borderColor: rgb(0, 0, 1), borderWidth: 2, rotate: degrees(90), font: ubuntuFont, })This will create a new widget for this text field. Parameters: NameTypeDescriptionpage PDFPage The page to which this text field widget should be added. options? FieldAppearanceOptions The options to be used when adding this text field widget. Returns: void defaultUpdateAppearances▸ defaultUpdateAppearances(font: PDFFont): void Overrides void Defined in Update the appearance streams for each of this text field's widgets using the default appearance provider for text fields. For example: const helvetica = await pdfDoc.embedFont(StandardFonts.Helvetica) const textField = form.getTextField('some.text.field') textField.defaultUpdateAppearances(helvetica)Parameters: NameTypeDescriptionfont PDFFont The font to be used for creating the appearance streams. Returns: void disableCombing▸ disableCombing(): void Defined in Turn off combing for this text field. For example: const textField = form.getTextField('some.text.field') textField.disableCombing()See and for more information about what combing is. This method will mark this text field as dirty. See for more details about what this means. Returns: void disableExporting▸ disableExporting(): void Inherited from PDFField. Defined in 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 disableFileSelection▸ disableFileSelection(): void Defined in Indicate that this text field is not intended to store a file path. For example: const textField = form.getTextField('some.text.field') textField.disableFileSelection()Returns: void disableMultiline▸ disableMultiline(): void Defined in Display each line of text on the same line when this field is displayed in a PDF reader. For example: const textField = form.getTextField('some.text.field') textField.disableMultiline()This method will mark this text field as dirty. See for more details about what this means. Returns: void disablePassword▸ disablePassword(): void Defined in Indicate that this text field is not intended for storing a secure password. For example: const textField = form.getTextField('some.text.field') textField.disablePassword()Returns: void disableReadOnly▸ disableReadOnly(): void Inherited from PDFField. Defined in 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. Defined in 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 disableRichFormatting▸ disableRichFormatting(): void Defined in Indicate that this is a standard text field that does not XFA data (rich text). For example: const textField = form.getTextField('some.text.field') textField.disableRichFormatting()Returns: void disableScrolling▸ disableScrolling(): void Defined in Do not allow PDF readers to present a scroll bar to the user when the contents of this text field do not fit within its view bounds. For example: const textField = form.getTextField('some.text.field') textField.disableScrolling()Returns: void disableSpellChecking▸ disableSpellChecking(): void Defined in Do not allow PDF readers to spell check the text entered in this field. For example: const textField = form.getTextField('some.text.field') textField.disableSpellChecking()Returns: void enableCombing▸ enableCombing(): void Defined in Split this field into n equal size cells with one character in each (where n is equal to the max length of the text field). This will cause all characters in the field to be displayed an equal distance apart from one another. For example: const textField = form.getTextField('some.text.field') textField.enableCombing()In addition to calling this method, text fields must have a max length defined in order to be combed (see ). This method will also call the following three methods internally: This method will mark this text field as dirty. See for more details about what this means. Returns: void enableExporting▸ enableExporting(): void Inherited from PDFField. Defined in 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 enableFileSelection▸ enableFileSelection(): void Defined in Indicate that this text field is intended to store a file path. The contents of the file stored at that path should be submitted as the value of the field. For example: const textField = form.getTextField('some.text.field') textField.enableFileSelection()Returns: void enableMultiline▸ enableMultiline(): void Defined in Display each line of text on a new line when this field is displayed in a PDF reader. For example: const textField = form.getTextField('some.text.field') textField.enableMultiline()This method will mark this text field as dirty. See for more details about what this means. Returns: void enablePassword▸ enablePassword(): void Defined in Indicate that this text field is intended for storing a secure password. For example: const textField = form.getTextField('some.text.field') textField.enablePassword()Values entered into password text fields should not be displayed on the screen by PDF readers. Most PDF readers will display the value as asterisks or bullets. PDF readers should never store values entered by the user into password text fields. Similarly, applications should not write data to a password text field. Please note that this method does not cause entered values to be encrypted or secured in any way! It simply sets a flag that PDF software and readers can access to determine the purpose of this field. Returns: void enableReadOnly▸ enableReadOnly(): void Inherited from PDFField. Defined in 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. Defined in Require this field to have a value when the form is submitted. For example: const field = form.getField('some.field') field.enableRequired()Returns: void enableRichFormatting▸ enableRichFormatting(): void Defined in Indicate that this field contains XFA data - or rich text. For example: const textField = form.getTextField('some.text.field') textField.enableRichFormatting()Note that pdf-lib does not support reading or writing rich text fields. Nor do most PDF readers and writers. Rich text fields are based on XFA (XML Forms Architecture). Relatively few PDFs use rich text fields or XFA. Unlike PDF itself, XFA is not an ISO standard. XFA has been deprecated in PDF 2.0: Returns: void enableScrolling▸ enableScrolling(): void Defined in Allow PDF readers to present a scroll bar to the user when the contents of this text field do not fit within its view bounds. For example: const textField = form.getTextField('some.text.field') textField.enableScrolling()A horizontal scroll bar should be shown for singleline fields. A vertical scroll bar should be shown for multiline fields. Returns: void enableSpellChecking▸ enableSpellChecking(): void Defined in Allow PDF readers to spell check the text entered in this field. For example: const textField = form.getTextField('some.text.field') textField.enableSpellChecking()Returns: void getAlignment▸ getAlignment(): TextAlignment Defined in Get the alignment for this text field. This value represents the justification of the text when it is displayed to the user in PDF readers. There are three possible alignments: left, center, and right. For example: const textField = form.getTextField('some.text.field') const alignment = textField.getAlignment() if (alignment === TextAlignment.Left) console.log('Text is left justified') if (alignment === TextAlignment.Center) console.log('Text is centered') if (alignment === TextAlignment.Right) console.log('Text is right justified')Returns: TextAlignment The alignment of this text field. getMaxLength▸ getMaxLength(): number | undefined Defined in Get the maximum length of this field. This value represents the maximum number of characters that can be typed into this field by the user. If this field does not have a maximum length, undefined is returned. For example: const textField = form.getTextField('some.text.field') const maxLength = textField.getMaxLength() if (maxLength === undefined) console.log('No max length') else console.log(`Max length is ${maxLength}`)Returns: number | undefined The maximum number of characters allowed in this field, or undefined if no limit exists. getName▸ getName(): string Inherited from PDFField. Defined in 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. getText▸ getText(): string | undefined Defined in Get the text that this field contains. This text is visible to users who view this field in a PDF reader. For example: const textField = form.getTextField('some.text.field') const text = textField.getText() console.log('Text field contents:', text)Note that if this text field contains no underlying value, undefined will be returned. Text fields may also contain an underlying value that is simply an empty string (''). This detail is largely irrelevant for most applications. In general, you'll want to treat both cases the same way and simply consider the text field to be empty. In either case, the text field will appear empty to users when viewed in a PDF reader. An error will be thrown if this is a rich text field. pdf-lib does not support reading rich text fields. Nor do most PDF readers and writers. Rich text fields are based on XFA (XML Forms Architecture). Relatively few PDFs use rich text fields or XFA. Unlike PDF itself, XFA is not an ISO standard. XFA has been deprecated in PDF 2.0: Returns: string | undefined The text contained in this text field. isCombed▸ isCombed(): boolean Defined in Returns true if this is a combed text field. This means that the field is split into n equal size cells with one character in each (where n is equal to the max length of the text field). The result is that all characters in this field are displayed an equal distance apart from one another. See and . For example: const textField = form.getTextField('some.text.field') if (textField.isCombed()) console.log('Combing is enabled')Note that in order for a text field to be combed, the following must be true (in addition to enabling combing): It must not be a multiline field (see ) It must not be a password field (see ) It must not be a file selector field (see ) It must have a max length defined (see ) Returns: boolean Whether or not this field is combed. isExported▸ isExported(): boolean Inherited from PDFField. Defined in Returns true if this field's value should be exported when the form is submitted. See and . 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. isFileSelector▸ isFileSelector(): boolean Defined in Returns true if the contents of this text field represent a file path. See and . For example: const textField = form.getTextField('some.text.field') if (textField.isFileSelector()) console.log('Is a file selector')Returns: boolean Whether or not this field should contain file paths. isMultiline▸ isMultiline(): boolean Defined in Returns true if each line of text is shown on a new line when this field is displayed in a PDF reader. The alternative is that all lines of text are merged onto a single line when displayed. See and . For example: const textField = form.getTextField('some.text.field') if (textField.isMultiline()) console.log('Multiline is enabled')Returns: boolean Whether or not this is a multiline text field. isPassword▸ isPassword(): boolean Defined in Returns true if this is a password text field. This means that the field is intended for storing a secure password. See and . For example: const textField = form.getTextField('some.text.field') if (textField.isPassword()) console.log('Password is enabled')Returns: boolean Whether or not this is a password text field. isReadOnly▸ isReadOnly(): boolean Inherited from PDFField. Defined in 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 and . 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. Defined in Returns true if this field must have a value when the form is submitted. See and . 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. isRichFormatted▸ isRichFormatted(): boolean Defined in Returns true if this text field contains rich text. See and . For example: const textField = form.getTextField('some.text.field') if (textField.isRichFormatted()) console.log('Rich formatting enabled')Returns: boolean Whether or not this field contains rich text. isScrollable▸ isScrollable(): boolean Defined in Returns true if PDF readers should allow the user to scroll the text field when its contents do not fit within the field's view bounds. See and . For example: const textField = form.getTextField('some.text.field') if (textField.isScrollable()) console.log('Scrolling is enabled')Returns: boolean Whether or not the field is scrollable in PDF readers. isSpellChecked▸ isSpellChecked(): boolean Defined in Returns true if the text entered in this field should be spell checked by PDF readers. See and . For example: const textField = form.getTextField('some.text.field') if (textField.isSpellChecked()) console.log('Spell checking is enabled')Returns: boolean Whether or not this field should be spell checked. needsAppearancesUpdate▸ needsAppearancesUpdate(): boolean Overrides void Defined in Returns true if this text field has been marked as dirty, or if any of this text field's widgets do not have an appearance stream. For example: const textField = form.getTextField('some.text.field') if (textField.needsAppearancesUpdate()) console.log('Needs update')Returns: boolean Whether or not this text field needs an appearance update. removeMaxLength▸ removeMaxLength(): void Defined in Remove the maximum length for this text field. This allows any number of characters to be typed into this field by the user. For example: const textField = form.getTextField('some.text.field') textField.removeMaxLength()Calling this method is equivalent to passing undefined to . Returns: void setAlignment▸ setAlignment(alignment: TextAlignment): void Defined in Set the alignment for this text field. This will determine the justification of the text when it is displayed to the user in PDF readers. There are three possible alignments: left, center, and right. For example: const textField = form.getTextField('some.text.field') // Text will be left justified when displayed textField.setAlignment(TextAlignment.Left) // Text will be centered when displayed textField.setAlignment(TextAlignment.Center) // Text will be right justified when displayed textField.setAlignment(TextAlignment.Right)This method will mark this text field as dirty. See for more details about what this means. Parameters: NameTypeDescriptionalignment TextAlignment The alignment for this text field. Returns: void setFontSize▸ setFontSize(fontSize: number): void Defined in Set the font size for this field. Larger font sizes will result in larger text being displayed when PDF readers render this text field. Font sizes may be integer or floating point numbers. Supplying a negative font size will cause this method to throw an error. For example: const textField = form.getTextField('some.text.field') textField.setFontSize(4) textField.setFontSize(15.7)This method depends upon the existence of a default appearance (/DA) string. If this field does not have a default appearance string, or that string does not contain a font size (via the Tf operator), then this method will throw an error. Parameters: NameTypeDescriptionfontSize number The font size to be used when rendering text in this field. Returns: void setImage▸ setImage(image: PDFImage): void Defined in Display an image inside the bounds of this text field's widgets. For example: const pngImage = await pdfDoc.embedPng(...) const textField = form.getTextField('some.text.field') textField.setImage(pngImage)This will update the appearances streams for each of this text field's widgets. Parameters: NameTypeDescriptionimage PDFImage The image that should be displayed. Returns: void setMaxLength▸ setMaxLength(maxLength?: undefined | number): void Defined in Set the maximum length of this field. This limits the number of characters that can be typed into this field by the user. This also limits the length of the string that can be passed to . This limit can be removed by passing undefined as maxLength. For example: const textField = form.getTextField('some.text.field') // Allow between 0 and 5 characters to be entered textField.setMaxLength(5) // Allow any number of characters to be entered textField.setMaxLength(undefined)This method will mark this text field as dirty. See for more details about what this means. Parameters: NameTypeDescriptionmaxLength? undefined | number The maximum number of characters allowed in this field, or undefined to remove the limit. Returns: void setText▸ setText(text: string | undefined): void Defined in Set the text for this field. This operation is analogous to a human user clicking on the text field in a PDF reader and typing in text via their keyboard. This method will update the underlying state of the text field to indicate what text has been set. PDF libraries and readers will be able to extract these values from the saved document and determine what text was set. For example: const textField = form.getTextField('best.superhero.text.field') textField.setText('One Punch Man')This method will mark this text field as dirty, causing its appearance streams to be updated when either or is called. The updated streams will display the text this field contains inside the widgets of this text field. IMPORTANT: The default font used to update appearance streams is . Note that this is a WinAnsi font. This means that encoding errors will be thrown if this field contains text outside the WinAnsi character set (the latin alphabet). Embedding a custom font and passing it to or allows you to generate appearance streams with characters outside the latin alphabet (assuming the custom font supports them). If this is a rich text field, it will be converted to a standard text field in order to set the text. pdf-lib does not support writing rich text strings. Nor do most PDF readers and writers. See for more information about rich text fields and their deprecation in PDF 2.0. Parameters: NameTypeDescriptiontext string | undefined The text this field should contain. Returns: void updateAppearances▸ updateAppearances(font: PDFFont, provider?: ‹PDFTextField›): void Defined in Update the appearance streams for each of this text field's widgets using the given appearance provider. If no provider is passed, the default appearance provider for text fields will be used. For example: const helvetica = await pdfDoc.embedFont(StandardFonts.Helvetica) const textField = form.getTextField('some.text.field') textField.updateAppearances(helvetica, (field, widget, font) => { ... return drawTextField(...) })Parameters: NameTypeDescriptionfont PDFFont The font to be used for creating the appearance streams. provider? ‹PDFTextField› Optionally, the appearance provider to be used for generating the contents of the appearance streams. Returns: void Static of▸ of(acroText: PDFAcroText, ref: PDFRef, doc: PDFDocument): PDFTextField‹› Defined in NOTE: You probably don't want to call this method directly. Instead, consider using the method, which will create an instance of PDFTextField for you. Create an instance of PDFTextField from an existing acroText and ref Parameters: NameTypeDescriptionacroText PDFAcroText The underlying PDFAcroText for this text field. ref PDFRef The unique reference for this text field. doc PDFDocument The document to which this text field will belong. Returns: PDFTextField‹› ← PDFSignatureViewerPreferences → (责任编辑：) |