I'm not sure how to access the DHTML and Advanced DHTML viewers from code. The main differences that you need to be concerned with are where the processing to render the report occur.
Crystal Report Viewer: A component that comes with Visual Studio. This is used for displaying reports from an ASP.NET or WinForms program. It is not a separate installation on the user's workstation. Report rendering occurs inside the component.
ActiveX Viewer: Available in InfoView. An ActiveX component that will be installed on the user's computer the first time it's accessed. Report rendering occurs on the user's workstation inside the component.
DHTML Viewer: Available in InfoView. Report rendering occurs on the web server. This has all of the functionality of the ActiveX viewer and is great for users who aren't allowed to install components on their workstations. However, it will take longer for the report to appear than with the other viewers.
Advanced DHTML Viewer: Like the DHTML viewer but with added search capabilities based on the specific fields that are in the report.
-Dell