The workhorse of data controls is the data grid or grid view. Given the advent of Silverlight 3, just about all of the Microsoft-oriented controls vendors have revamped their product lines. I asked Telerik, one of the leaders in this space, how its RadGridView for Silverlight improves on the Microsoft Silverlight 3 DataGrid. They were only too happy to tell me.
First of all, RadGridView comes with Excel-like filtering, right out of the box (see figure below). You can add such functionality to the Microsoft DataGrid yourself, but it would take a significant amount of work.
In addition, RadGridView does drag-and-drop, chainable grouping with aggregate functions displayed in groups and footers, and comes with five themes, three of which are modeled on Microsoft Office styles. The most impressive improvement I saw in RadGridView, however, is its performance for large numbers of rows.
If you fill a Microsoft DataGrid with 50,000 rows of data and try to scroll through them, you'll be in for some frustration as the DataGrid tries to manipulate 50,000 rows. If you try the same experiment with RadGridView, you'll find that only the row number updates onscreen as you scroll through the data; when you get to where you want, the view updates almost instantaneously. This data virtualization comes courtesy of Telerik's new LINQ-based data engine; the same engine improves sorting and filtering and powers the aggregate function display.
For more detail and some demos, see Telerik's sales page for the RadGridView.