PDFNet SDK is a high-quality, industry-strength PDF library meeting
requirements of the most demanding and diverse applications. Using
PDFNet components you can write stand-alone, cross-platform, and
reliable commercial applications that can read, write, edit, print
and display PDF documents. PDFNet SDK is available as a .NET component
and as a cross-platform Java and C/C++ library. More
info.
PDFView sample project
illustrates how to add PDF viewing and editing capability in
client applications.