Nrapid, working with page breaks and report options

So far we been working with reports and exploring a couple of options on how to group data, customize dialogs and so on, but we never talk about printing.

While there isn’t much to say about printing when it comes to standard reports, I mean, you execute the report, press print and you are pretty much set. When it comes to complex reports, we have a couple of options.

In this post I’m going to talk about page breaks and how they behave in reports that contain grouped data.

Continuing with the categories and products example, we want to print each category in her own page (a group per page) this means that we need a page break after each group of data.

By default, NRapid will not going to add page breaks after groups, because internally doesn’t knows what a group is. It just going to emit standard html based on the default style sheet or the specified raw style. The easiest way to insert page breaks, is by building the report using the “table per group” approach, and tells to NRapid please insert a page break after each table in this report. This can be done with a couple of lines of code that may look like this.

When you execute the report, you are not going to see anything special; the only thing that changes is a header that is used by printers.

If you print the report, you should get something like this:

Something that worth to mention, in all the examples we have seen there is a common anti pattern called select n + 1. This can be fixed easily using datasets instead of data tables, hit the database ones and then work with the data set in memory.

You can get the source code of NRapid from here

And the sample app from here

The Northwind database is available from download at http://www.microsoft.com/en-us/download/details.aspx?id=23654

Comments

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