Expressions Reference Overview
Expressions are written in Telerik Reporting scripting language. The language is based on mathematical expressions, and is case insensitive.
When you write an expression, you have access to many built-in fields, collections, and functions that you can use alone or combine with other terms. You can add function calls, operators, constants, fields, parameters, items from the built-in collections to an expression. Built-in function calls include aggregation, commonly used utility functions, and conversion methods. You can also add references to functions defined in your code (see user functions).