Expression Syntax

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An expression formula is a text string that specifies a series of operations on source data. Expressions can combine fields, use input, constants, and operators with a wide range of built-in functions for calculations, text processing, conditional logic, and summaries.

This topic describes syntax rules and elements you can use to construct report expressions.

In this topic…

• General Syntax Rules
  • Case Sensitivity
  • Formatting
  • Escaping Reserved Characters
  • Comments
• Expression Elements
  • Report Items
  • Fields/Parameters
  • Predefined Values
  • Constants
  • Functions
  • Operators
  • Variables

General Syntax Rules

Follow rules and conventions described in this help topic when you write expressions:

Case Sensitivity

Keywords, operators, and function names are case-insensitive.

The case sensitivity of field names and parameter values depends entirely on the underlying data source. For example, Microsoft SQL Server Express treats uppercase and lowercase characters identically unless explicitly configured otherwise.

Formatting

An expression can be a single line or span multiple lines. Whitespace and line breaks between expression elements are ignored.

You can align operators, indent nested terms, or group sub-expressions for maximum readability.

Escaping Reserved Characters

Use the following patterns to escape characters with reserved meaning inside a string literal:

• Apostrophe: Double the apostrophe (''). For example: 'McDonald''s'.
• Object reference: Escape surrounding brackets with backslashes (\[ and \]) to prevent text from being interpreted as a field, report item, or variable. For example, '\[UnitPrice\]'.

Comments

Use comments to annotate an expression or temporarily exclude part of its code from evaluation. A comment starts with /* and ends with */ and can span multiple lines:

Expression

/* Applies a discount if the customer qualifies
    for the loyalty program */
Iif([Customer.IsLoyaltyMember], [Amount] * 0.9, [Amount])

Expression Elements

Expression elements are the building blocks you can combine to construct a formula. The following sections describe available elements and their syntax:

• Report Items
• Fields/Parameters
• Predefined Values
• Constants
• Functions
• Operators
• Variables

Report Items

To reference the value of a report band or a report property, use the [ReportItems.<path>] syntax.

<path> is the unique identifier of a target element/property. For example, the following expression returns the report’s top margin:

Expression

[ReportItems.TopMargin]

Select Report Items in the Element Categories panel to see a complete list of available report items:

Fields/Parameters

To reference a data field or calculated field, enclose its name in square brackets ([<field name>]). For example, the following expression returns the ProductID field value:

Expression

[ProductID]

To reference a field from a specific data member (a table or list within a data source), prefix the field name with the square-bracketed data member name separated by a period. For example:

Expression

[Orders].[ShipAddress]

To reference a report parameter, add a question mark (?) before the parameter’s name. For example, the following expression returns the discountParameter value:

Expression

?discountParameter

Select Fields in the Element Categories panel to see a complete list of available data fields and report parameters:

Summaries

Use the following syntax to construct an expression that aggregates values:

Expression

[<Collection>][<Condition>].<Function>(<Expression>)

Collection

A master-detail relationship name.

To calculate an aggregated value against all records, use empty square brackets ([]).

Condition

An expression that filters records used to calculate an aggregate function.

To calculate aggregates within groups, use the ^ operator to refer to the processed group.

To calculate an aggregated value against all records, use empty square brackets ([]).

Function

A built-in function that aggregates values that match the Condition.

Expression

A field name, parameter, or complex expression.

Summary Examples

Expression	Result
[CategoriesProducts][[CategoryId] > 5].Count()	The number of products where CategoryId is greater than 5.
[][[CategoryID] == 5].Sum([UnitPrice] * [UnitsInStock])	The total inventory value of all products in category 5.
[][[^.CategoryID] == [CategoryID]].Sum([UnitPrice])	The total unit price of all products that belong to the current category.
[].Count()	The total number of records in the report.

Predefined Values

Certain report element properties — such as colors, border style, or text alignment — support only a fixed set of values. Select Values in the Element Categories panel to see a complete list of values available for the selected property:

Note

If the selected element property is not associated with a fixed list of values, the Values group is not displayed.

Predefined values are referenced as string literals enclosed in apostrophes ('...').

Properties can accept more than one value simultaneously. To reference multiple values, list them within the same string literal and separate them with commas. For example, the following expression sets both left and right borders:

Expression

'Left, Right'

Constants

A constant is a literal value written directly in an expression. The following table lists supported constant types and their syntax:

Type	Syntax	Example
String	Enclose text in apostrophes ('...'). To use characters with reserved meaning within a string literal, escape them.	'VCL Reports' 'Don''t'
Numeric	A value without a suffix is an Int32 (an integer value) or Double (a double-precision floating-point value). Append a suffix to specify another type: s — Int16, b — Byte, f — Single, m — Decimal.	1 1.0f
Date and time	Enclose an ISO 8601 date or date-time value (yyyy-MM-dd, yyyy-MM-dd HH:mm:ss, or similar literals) in number signs (#...#).	#2026-09-22# #2026-09-22 14:23:41#
Boolean	Use the True or False keyword.	True
GUID	Enclose the value in curly braces ({...}). Use GUID constants only with the equality (==) or inequality (!=) operators.	{86573e14-88fc-4c51-8950-293118cdca88}
Null reference	Use the ? character. Use IsNull/IsNullOrEmpty functions instead of the ? null reference constant where possible.	[MiddleName] == ?

Functions

To call a built-in function, type its name followed by a comma-separated list of arguments in parentheses. For example, the following expression returns the trimmed value of the CompanyName field:

Expression

Trim([CompanyName])

Select Functions in the Element Categories panel to see a complete list of available functions, or expand the Functions node and select a category for easier navigation:

Refer to the following help topic for a full list of functions and usage examples: Built-in Expression Functions.

Operators

Operators combine operands (fields, parameters, constants, or entire functions) into a single expression.

Select Operators in the Element Categories panel to see a complete list of available operators:

Arithmetic Operators

Operator	Description	Example
+	Adds two numbers, or concatenates two strings.	[UnitPrice] + [Freight]
-	Subtracts one number from another. When - is placed before a single operand (as an unary operator), the operator negates the operand’s value.	[UnitPrice] - [Discount]
*	Multiplies two numbers.	[UnitPrice] * [Quantity]
/	Divides one number by another. If both operands are integers, the result is an integer (rounded down).	[Total]/[Count]
%	Divides one number by another and returns the remainder.	[Quantity] % 12

Comparison Operators

Operator	Description	Example
==	Returns True if both operands are equal.	[Country] == 'USA'
!=	Returns True if the operands are not equal.	[Country] != 'USA'
<, <=	Returns True if the left operand is less than (or less than or equal to) the right operand.	[Quantity] < 10
>, >=	Returns True if the left operand is greater than (or greater than or equal to) the right operand.	[Quantity] >= 10
Between (<low>, <high>)	Returns True if the tested value is greater than or equal to <low> and less than or equal to <high>.	[Amount] Between (100, 500)
In (<value1>, <value2>, ...)	Returns True if the tested value matches one of the listed values.	[Country] In ('USA', 'Canada', 'Mexico')
Like	Returns True if a string matches the specified pattern. Use % as a wildcard for any sequence of characters.	[Name] Like 'Jo%'

Logical Operators

Operator	Description	Example
And	Returns True if both Boolean operands are True (logical conjunction).	[InStock] And [Quantity] > 0
Or	Returns True if either Boolean operand is True (logical disjunction).	[IsLoyaltyMember] Or [Amount] > 1000
Not	Reverses the value of a Boolean operand (logical negation).	Not [Discontinued]

Bitwise Operators

Bitwise operators compare individual bits of two integer operands.

Operator	Description	Example
&	Bitwise AND. The result bit is 1 only when both operand bits are 1.	[Flags] & 4
\|	Bitwise inclusive OR. The result bit is 1 when either operand bit is 1.	[Flags] \| 4
^	Bitwise exclusive OR (XOR). The result bit is 1 when exactly one operand bit is 1.	[Flags] ^ 4

Operator Precedence

When an expression combines multiple operators, the report evaluates them in the following order (highest precedence first). Use parentheses (...) to override this order:

1. Parentheses (...)
2. Functions
3. In
4. Unary minus (-)
5. Not
6. *, /, %
7. Binary +, -
8. <, >, <=, >=
9. ==, !=
10. And
11. Or

Operators of the same precedence level are evaluated left to right.

Variables

To reference a data source variable, use the [DataSource.<name>] syntax. For example, the following expression returns the number of rows in the underlying data source:

Expression

[DataSource.RowCount]

The following variables are available:

Variable	Description
DataSource.CurrentRowIndex	A zero-based index of the current row within the data source.
DataSource.RowCount	The total number of rows in the data source.
DataSource.CurrentRowHierarchyLevel	The nesting level of the current row in a hierarchical (master-detail) data source. The top-level row is 0.
DataSource.IsFirstRow	Returns True if the current row is the first row in the data source.
DataSource.IsLastRow	Returns True if the current row is the last row in the data source.

Select Variables in the Element Categories panel to see a complete list of available data source variables: