Thank you for your questions and feedback.
Generally speaking, the only difference between using the Telerik Reports in a Windows Forms app and in an ASP.NET app is in the ReportViewer control you need to use. This is from Report's point of view - creating a report, customizing its appearance and connection to a data source is the same, regardless of the application.
When it comes to "Print customers", things are a bit more complicated. First of all, the actual printing is performed on the client (browser) and the reports are rendered on the server. So when the user presses the print button, the browser posts back to the server, the report gets generated and returned to the client (browsers print only what they display so I assume you've rendered the report in HTML).
Only then you should instruct the browser to print the HTML. A possible solution I can think of is to use a hidden IFRAME; then on "Print customers" set the IFRAME.src
is the IFRAME instance.
Regarding the dummy data sources: actually, this thread was initiated by a developer that didn't want to connect to a real data source at design time but needed the Data Explorer support in order to create his/her reports easier. The dummy data source is a possible workaround that supplies the report designer with the needed schema. The bottom line is that you don't need any dummy data source at all.
About the "Object reference not set to an instance of an object" error in the HTML Preview and at runtime - the most possible reason I can guess is that you didn't connect any data source to your report. Please, check this and write back with more information.
In the upcoming service pack (to be released by the end of this week) the problem with the missing data adapters from the list of the available data sources will be fixed and I hope you'll have no more problems with it.
Your suggestion for the report designer are really good and we'll review them once again when planning the future versions.
the Telerik team