Saving Annotation (ink) on permanently on PDF

Can I save signature (ink annotation) on PDF permanently?

I used
m_doc.Save();

and able to save the annotations, but these the annotation are editable when ever I open the PDF.

Can we stop preventing editing saved annotation generally(ink annotations)?

Hi,
yes you should use
This method has been fixed in the last beta version : was corrupting text fields rendering.
You can safely use the beta, we are expecting to promote to stable version friday next week.

It would be great help if you can tell where exactly to call this method.

Hi,
it dipends on your needs.
For example you can lock annot after adding it with something like this :

Hi, i tried your solution before saving the pdf, but it did not work. My exact requirement is that i want to make the annotation just like text so that if someone opens it in pdf reader and they won't be able to delete that annotation. Right now, if i save it and open it on laptop, i can remove the annotation but text i can not remove.

You can call Page.FlatAnnots -> this will make the annotations part of the page content and cannot be removed.
but it will flatten all the annotations contained in this page
This method requires the premium license.