PdfRotationAngle API in JavaScript (ES5) PDF API control

// Load an existing PDF document
let document: PdfDocument = new PdfDocument(data, password);
// Access text box field
let field: PdfTextBoxField = document.form.fieldAt(0) as PdfTextBoxField;
// Gets the rotation of the field
let rotation: PdfRotationAngle = field.rotationAngle;
// Save the document
document.save('output.pdf');
// Destroy the document
document.destroy();