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Functions Reference

Updated on May 7, 2026

RadExpressionEditor provides a set of built-in functions organized into the following categories: Text, Aggregate, Date-Time, Logical, Math, and Other (Conversion). Each function is called by name in uppercase, followed by its arguments in parentheses.

All functions are case-insensitive. SUM(), Sum(), and sum() are equivalent.

Text Functions

Text functions perform string manipulation operations.

Function	Syntax	Return Type	Description
`TOSTR`	`TOSTR(Object)`	string	Returns a string representation of an object.
`TRIM`	`TRIM(String)`	string	Removes whitespace from the beginning and end of a string.
`LEN`	`LEN(String)`	int	Returns the number of characters in a string.
`FORMAT`	`FORMAT(FormatString, Value)`	string	Replaces the format item in a string with the text equivalent of a value. Uses .NET composite format strings, for example `FORMAT('{0:C}', [Price])`.
`SUBSTR`	`SUBSTR(String, StartIndex, Length)`	string	Retrieves a substring starting at the specified zero-based character position with the specified length.
`INSERT`	`INSERT(String1, StartIndex, String2)`	string	Inserts `String2` into `String1` at the zero-based position specified by `StartIndex`.
`LOWER`	`LOWER(String)`	string	Returns the string converted to lowercase.
`UPPER`	`UPPER(String)`	string	Returns the string converted to uppercase.
`PADLEFT`	`PADLEFT(String, TotalLength)`	string	Right-aligns the characters in the string by padding its left side with spaces up to the specified total length.
`PADRIGHT`	`PADRIGHT(String, TotalLength)`	string	Left-aligns the characters in the string by padding its right side with spaces up to the specified total length.
`REMOVE`	`REMOVE(String, StartIndex, Count)`	string	Deletes the specified number of characters from the string, beginning at the specified zero-based position.
`REPLACE`	`REPLACE(String, OldValue, NewValue)`	string	Returns a copy of `String` in which all occurrences of `OldValue` are replaced with `NewValue`.

Examples:

LOWER([ProductName])
SUBSTR([ProductName], 0, 3)
FORMAT('{0:N2}', [UnitPrice])
REPLACE([Description], 'old', 'new')
TRIM([CustomerName])
LEN([ProductName])
INSERT([Code], 0, 'PRD-')

Aggregate Functions

Aggregate functions compute a single value from a column across all rows. Pass a column reference as the argument.

Function	Syntax	Return Type	Description
`SUM`	`SUM([ColumnName])`	numeric	Computes the sum of values in the specified column.
`AVG`	`AVG([ColumnName])`	numeric	Computes the average of values in the specified column.
`MIN`	`MIN([ColumnName])`	varies	Returns the minimum value in the specified column.
`MAX`	`MAX([ColumnName])`	varies	Returns the maximum value in the specified column.
`COUNT`	`COUNT([ColumnName])`	int	Returns the number of values in the specified column.
`FIRST`	`FIRST([ColumnName])`	varies	Returns the first value in the specified column.
`LAST`	`LAST([ColumnName])`	varies	Returns the last value in the specified column.

Examples:

SUM([UnitPrice])
AVG([Quantity])
COUNT([OrderID])
MAX([OrderDate])
MIN([UnitPrice])

Date-Time Functions

Date-Time functions create, modify, and extract components from DateTime values.

Getting the Current Date and Time

Function	Syntax	Return Type	Description
`NOW`	`NOW()`	DateTime	Returns the current system date and time expressed as local time.
`TODAY`	`TODAY()`	DateTime	Returns the current date at midnight (time portion is 00:00:00).
`UTCNOW`	`UTCNOW()`	DateTime	Returns the current system date and time expressed as Coordinated Universal Time (UTC).

Adding Time Intervals

Function	Syntax	Return Type	Description
`ADDDAYS`	`ADDDAYS(DateTime, DaysToAdd)`	DateTime	Returns a date-time value offset by the specified number of days.
`ADDHOURS`	`ADDHOURS(DateTime, HoursToAdd)`	DateTime	Returns a date-time value offset by the specified number of hours.
`ADDMINUTES`	`ADDMINUTES(DateTime, MinutesToAdd)`	DateTime	Returns a date-time value offset by the specified number of minutes.
`ADDSECONDS`	`ADDSECONDS(DateTime, SecondsToAdd)`	DateTime	Returns a date-time value offset by the specified number of seconds.
`ADDMILLISECONDS`	`ADDMILLISECONDS(DateTime, MillisecondsToAdd)`	DateTime	Returns a date-time value offset by the specified number of milliseconds.
`ADDTICKS`	`ADDTICKS(DateTime, TicksToAdd)`	DateTime	Returns a date-time value offset by the specified number of ticks.
`ADDMONTHS`	`ADDMONTHS(DateTime, MonthsToAdd)`	DateTime	Returns a date-time value offset by the specified number of months.
`ADDYEARS`	`ADDYEARS(DateTime, YearsToAdd)`	DateTime	Returns a date-time value offset by the specified number of years.
`ADDTIMESPAN`	`ADDTIMESPAN(DateTime, TimeSpan)`	DateTime	Returns a date-time value offset by the specified `TimeSpan`.

Calculating Date Differences

These functions return the difference between two dates in the specified unit.

Function	Syntax	Return Type	Description
`DATEDIFFDAY`	`DATEDIFFDAY(StartDate, EndDate)`	double	Returns the number of day boundaries between two dates.
`DATEDIFFHOUR`	`DATEDIFFHOUR(StartDate, EndDate)`	double	Returns the number of hour boundaries between two dates.
`DATEDIFFMINUTE`	`DATEDIFFMINUTE(StartDate, EndDate)`	double	Returns the number of minute boundaries between two dates.
`DATEDIFFSECOND`	`DATEDIFFSECOND(StartDate, EndDate)`	double	Returns the number of second boundaries between two dates.
`DATEDIFFMILLISECOND`	`DATEDIFFMILLISECOND(StartDate, EndDate)`	double	Returns the number of millisecond boundaries between two dates.
`DATEDIFFTICK`	`DATEDIFFTICK(StartDate, EndDate)`	long	Returns the number of tick boundaries between two dates.

Extracting Date-Time Components

Function	Syntax	Return Type	Description
`GETDATE`	`GETDATE(DateTime)`	DateTime	Extracts the date portion (time set to midnight).
`GETDAY`	`GETDAY(DateTime)`	int	Extracts the day of the month (1-31).
`GETDAYOFWEEK`	`GETDAYOFWEEK(DateTime)`	DayOfWeek	Extracts the day of the week.
`GETDAYOFYEAR`	`GETDAYOFYEAR(DateTime)`	int	Extracts the day of the year (1-366).
`GETHOUR`	`GETHOUR(DateTime)`	int	Extracts the hour component (0-23).
`GETMINUTE`	`GETMINUTE(DateTime)`	int	Extracts the minute component (0-59).
`GETSECOND`	`GETSECOND(DateTime)`	int	Extracts the second component (0-59).
`GETMILLISECOND`	`GETMILLISECOND(DateTime)`	int	Extracts the millisecond component (0-999).
`GETMONTH`	`GETMONTH(DateTime)`	int	Extracts the month component (1-12).
`GETYEAR`	`GETYEAR(DateTime)`	int	Extracts the year component.
`GETTIMEOFDAY`	`GETTIMEOFDAY(DateTime)`	long	Extracts the time of day expressed in ticks.

Examples:

ADDDAYS([OrderDate], 30)
DATEDIFFDAY([OrderDate], NOW())
GETYEAR([OrderDate])
GETMONTH([ShippedDate])
ADDMONTHS(TODAY(), -6)

Logical Functions

Function	Syntax	Return Type	Description
`IIF`	`IIF(BooleanExpression, TruePart, FalsePart)`	object	Evaluates `BooleanExpression` and returns `TruePart` if true, or `FalsePart` if false.
`ISNULL`	`ISNULL(Value, ReplacementValue)`	object	Returns `Value` if it is not null. Otherwise, returns `ReplacementValue`.

Examples:

IIF([UnitPrice] > 100, 'Expensive', 'Affordable')
ISNULL([ShippedDate], #01/01/2000#)
IIF([Quantity] > 0 AND [UnitPrice] > 0, [Quantity] * [UnitPrice], 0)

Math Functions

Function	Syntax	Return Type	Description
`ABS`	`ABS(Value)`	numeric	Returns the absolute value of a number.
`CEILING`	`CEILING(Value)`	numeric	Returns the smallest integer greater than or equal to the specified number.
`FLOOR`	`FLOOR(Value)`	numeric	Returns the largest integer less than or equal to the specified number.
`ROUND`	`ROUND(Value)`	decimal	Rounds the value to the nearest integer.
`SIGN`	`SIGN(Value)`	int	Returns +1, 0, or -1 indicating the sign of the number.
`SQRT`	`SQRT(Value)`	double	Returns the square root of a number.
`POWER`	`POWER(Base, Exponent)`	double	Returns a number raised to the specified power.
`EXP`	`EXP(Value)`	double	Returns e raised to the specified power.
`LOG`	`LOG(Value)`	double	Returns the natural (base e) logarithm of a number.
`LOG10`	`LOG10(Value)`	double	Returns the base-10 logarithm of a number.
`BIGMUL`	`BIGMUL(Value1, Value2)`	long	Returns a 64-bit integer containing the full product of two 32-bit integers.
`RND`	`RND()`	double	Returns a random number greater than or equal to 0.0 and less than 1.0.
`SIN`	`SIN(Radians)`	double	Returns the sine of the specified angle in radians.
`COS`	`COS(Radians)`	double	Returns the cosine of the specified angle in radians.
`TAN`	`TAN(Radians)`	double	Returns the tangent of the specified angle in radians.
`ASIN`	`ASIN(Value)`	double	Returns the angle in radians whose sine is the specified value.
`ACOS`	`ACOS(Value)`	double	Returns the angle in radians whose cosine is the specified value.
`ATAN`	`ATAN(Value)`	double	Returns the angle in radians whose tangent is the specified value.
`SINH`	`SINH(Radians)`	double	Returns the hyperbolic sine of the specified angle in radians.
`COSH`	`COSH(Radians)`	double	Returns the hyperbolic cosine of the specified angle in radians.
`TANH`	`TANH(Radians)`	double	Returns the hyperbolic tangent of the specified angle in radians.

Examples:

ABS([Quantity] - [Expected])
ROUND([UnitPrice] * 1.1)
POWER([Value], 2)
SQRT([Area])
CEILING([Total] / 10)

Conversion Functions

Conversion functions convert an expression to a specific .NET data type.

Function	Syntax	Return Type	Description
`CINT`	`CINT(Expression)`	System.Int32	Converts the expression to a 32-bit integer.
`CDBL`	`CDBL(Expression)`	System.Double	Converts the expression to a double-precision floating-point number.
`CBOOL`	`CBOOL(Expression)`	System.Boolean	Converts the expression to a Boolean value.
`CDATE`	`CDATE(Expression)`	System.DateTime	Converts the expression to a DateTime value.
`CSTR`	`CSTR(Expression)`	System.String	Converts the expression to a string value.

Examples:

CINT([Quantity])
CDBL([UnitPrice]) * 1.5
CDATE('2025-01-15')
CSTR([ProductID])
IIF(CBOOL([IsActive]), 'Active', 'Inactive')