MS Visio is a widely used application for creating a multitude of diagrams such as flowcharts, business flow diagrams, etc. However, in various cases, you may need to convert the diagram files to other file formats. For example, when sharing the diagrams you can convert them to a PDF file. On the other hand, you can convert a diagram to an image for embedding it into your web or desktop application. In this article, we will target Visio diagram to PDF conversion programmatically. Particularly, you will learn how to convert VSDX or VSD files to PDF using C#.