You can save the form fields, signatures, and annotations to the PDF document on the server side of the PDF viewer control using the API in the button click. For this, modify the web action method in the web API controller of the PDF viewer control. Following is the server-side code snippet for the Download action method of the API controller.
Client-side code for saving the PDF document
In the following sample clicking ‘Save PDF Document’ button and Download icon in the PDF Viewer toolbar will save the PDF document in server side:
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