public void FlattenControls()
Public Sub FlattenControls
Flattening locks controls from editing. Flattening can significantly reduce file size if RemoveUnusedObjects property is set to true.
This method enumerates all controls in the document and flattens every control in 2 steps:
This method can change graphics state of the pages. Call it right before saving of the document to avoid side effects.
Flattening of signature fields without appearance stream is not supported yet.