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Can the API functions read annotation information from PDF documents?

Question:

 Can the API functions read annotation information from PDF documents?

Answer:

Yes, but the low-level API functions must be used for this purpose, as opposed to the Hi-Level API functions, which do not support it. This is because most annotation types have mutliple properties that can be configured in multiple ways. If all possibilites were implemented then the overall size would become unnecessarily large and problematic. The mechanism to create annotations is provided and it supplies most - but not all - usable possibilites.

The low-level API provided in xcpro can be used to manipulate annotations. This requires good knowledge of the PDF format and a lot of additional coding - but the end result is full control of PDF files. Please note that xcpro and PDF-XChange Viewer use different code to handle PDF files, and therefore it is not possible to copy code between them.

Additionally, please note that the low-level API is a powerful set of functions that enables developers to make changes at the most fundamental level of PDF files. Whilst this is very useful from a developmental perspective, indiscriminate use will undoubtedly lead to file corruption and other issues. Tracker Software will not accept any responsibility, should such problems arise, and we advise emphatically that developers exercise caution and patience when the low-level API is utilized. 

If you request support in relation to the low-level API then we will expect you to have a thorough working knowledge of PDF and the associated Adobe documentation. The best references for this are: 

The Adobe PDF Reference, Sixth Edition and

Document Management – Portable Document Format – Part 1: PDF 1.7

These documents provide a comprehensive description/analysis of PDF and are intended for developers of PDF-related software. They contain sufficient information to enable developers to write applications that read PDF files and/or modify their content. 

JavaScript can also be employed to manipulate PDF files. Authors, form designers and plug-in developers can utilize JavaScript extensions in order to expose most of the functionality of PDF-XChange Viewer and its plug-ins. The following document describes the JavaScript for Acrobat API. All objects, properties and methods are documented and extensive code examples are included:

JavaScript for Acrobat API Reference, Version 8

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