PDF Metamorphosis .Net is a cross-platform .NET library that allows your applications to convert any document to PDF format. After adding a reference to "SautinSoft.PdfMetamorphosis.dll" and entering 3-4 lines of C#, you can use the API in your applications:
PDF documents using a proprietary PDF class. You can choose the version for the output PDF: 1.2 -1.7, PDF/A