What you can do with expressions
Supports built-in RDL reporting collections such as Globals, User, ReportItems, Parameters, Fields, DataSets, DataSources, Variables, and built-in fields. You can include the ReportItem collection to summarize items on the page and display it in a page header or page footer.
Custom code assembly
Renders the custom code assemblies used to maintain code in a single place and allows you to share them in multiple reports. The Report Viewer allows you to display your own components as images in reports.
Allows you to highlight or style table rows, chart data points, series, text box values, and any data in the report based on specified conditional expressions. You can use operators and constants defined in the Visual Basic runtime library in a conditional or standard expression.
Renders additional fields to create new values that are derived from the data set. It can perform arithmetic and other mathematical operations; manipulate text, date, and geographic information; and use branching logic to evaluate your data and return different results. The output of a calculated field can then be displayed in any property of a report item.
Visual Basic functions
Processes and renders Microsoft Visual Basic runtime library functions and .NET Framework common language runtime classes (CLR) in math and convert namespaces. These functions can be used to manipulate data that will be displayed in text boxes, parameters, properties, expression, and other areas of a report.
You can use built-in SQL RDL aggregate functions in expressions to include aggregated values in your report. The functions used to calculate summaries, count rows, look up values in the data set, and more are supported in the WPF Report Viewer.