Annotation Rotation ​

Annotation rotation provides the functionality to rotate standard stamp annotations, custom stamp annotations, image annotations, and electronic signature annotations, allowing users to rotate annotations through a full range (-180~180 degrees). ComPDFKit offers convenient APIs for rotating annotations, along with demo demonstrations.

Rotating Annotations Programmatically

To rotate the annotation programmatically, you set it using two methods: SetSourceRect in the CPDFAnnotation class and SetRotation in the CPDFAnnotationRotator class.

• CPDFAnnotation.SetSourceRect

  The rectangular Rect before rotation. It's worth noting that this only needs to be refreshed when the annotation is scaled or moved, not when it is rotated.

• CPDFAnnotationRotator.SetRotation

  Sets the rotation angle of the annotation in degrees, with a range from -180 to 180.

Here is the example code for annotation rotation:

// Obtain the page object.
CPDFPage page = document.PageAtIndex(0);

// Create standard stamp annotation.
CPDFStampAnnotation standard = page.CreateAnnot(C_ANNOTATION_TYPE.C_ANNOTATION_STAMP) as CPDFStampAnnotation;
standard.SetStandardStamp("Approved");
 
// Sets the rectangle before annotation rotation.
standard.SetSourceRect(new CRect(100, 150, 250, 100));

// Sets the rotation Angle of the annotation.
standard.AnnotationRotator.SetRotation(45);

standard.UpdateAp();