October 2013

Adding links to PDF files is very straight forward. A link in a PDF is actually an annotation and is placed on top of the content that you wish to link. These hotspot links can be added using the following functions: Read more about annotations and hotspot links. An example of how to use the […]

Currently it is only possible to replace simple text that has not been encoded using Foxit Quick PDF Library using the scripting feature which uses Foxit Quick PDF Library behind the scenes. The function that lets you replace text is the ReplaceTag function. Basically, it is possible to replace some text in a PDF file […]

There isn’t an easy way to check if a PDF contains compressed elements or not. There is not a PDF wide compression option, instead various different objects and streams in PDF files can be compressed individually, using different compression methods. So if you wanted to determine if a PDF contained any compression at all you […]

When you use the SignFile function to add a digital signature to a PDF it adds an invisible digital signature which is not shown on any of the pages in the document. Instead the digital signature can be viewed by opening the PDF in Adobe Reader, Adobe Acrobat or another PDF editing application, and clicking […]

The SignFile function in Foxit Quick PDF Library lets you sign PDF files using the PKCS#12 format (containing a certificate and private key). But sometimes more advanced signing options are required. This is why we’ve added two new functions: SetSignProcessPassthrough and GetSignProcessByteRange. These functions let you sign PDF files using signatures that were created externally. These […]

After signing a PDF file and then opening it in Adobe Reader or Adobe Acrobat the following message may be shown just below the toolbar: This message does not indicate that the digital signature is invalid or corrupt. Instead it’s a poorly worded message from Adobe that causes unnecessary alarm. If you click on the […]