updatePageAnnotation

Modifies an existing annotation on a specific page.

Signature


updatePageAnnotation(
  doc: PdfDocumentObject,
  page: PdfPageObject,
  annotation: PdfAnnotationObject
): PdfTask<boolean>;

Description

This method finds an existing annotation by its id and updates its properties with the values from the provided annotation object. This allows you to change an annotation’s position, color, content, or any other attribute.

Like createPageAnnotation, this modifies the document in memory. Use saveAsCopy to generate a file with the changes.

Parameters

Name	Type	Description
`doc`	`PdfDocumentObject`	The handle of the document to modify.
`page`	`PdfPageObject`	The page where the annotation exists.
`annotation`	`PdfAnnotationObject`	The modified annotation object. It must have the same `id` as the annotation you wish to update.

Returns

PdfTask<boolean>

A Task that resolves with true if the annotation was successfully found and updated.

Example


// Assuming 'engine', 'document', and 'page' are available
 
async function changeAnnotationColor(annotation) {
  // Create a modified copy of the annotation
  const updatedAnnotation = {
    ...annotation,
    color: '#FF0000', // Change color to red
    rect: { // Also move it
      ...annotation.rect,
      origin: { x: annotation.rect.origin.x, y: annotation.rect.origin.y + 10 }
    }
  };
 
  try {
    const success = await engine.updatePageAnnotation(document, page, updatedAnnotation).toPromise();
    if (success) {
      console.log(`Annotation ${annotation.id} was updated.`);
      // Re-render the page or just the annotation to see the change
    }
  } catch (error) {
    console.error('Failed to update annotation:', error);
  }
}