Component Reference

Properties for TRpExpression


Name Internal Name Type Description
Expression Expression WideString Expression, the result of evaluating the expression will be printed (except if it's an aggregate)
Data Type DataType TRpParamType Used for formatting output, if you specify a data type and the expression value is NULL it's replaced with the type equivalent for formating, this is specially usefull for numeric values
Display Format DisplayFormat String

Formating mask, the value to print will be formated with this string, depending on the data type of the value the string have diferent meanings.

For example for a DateTime value you can use the format string: 'dd/mm/yyyy hh:nn:ss', for a number: '###,###0.00', where the , says the use of thousand separator, the 0 are required format positions and # are not required format positions.

The engine will use FormatStr function, see documentation, but if the first character is a *, the FormatNum function will be used (only for numbers), using the mask without the first char.

Multi page MultiPage Boolean If true, then the print value (usually a string) will print in diferent pages if needed, usually you set autoexpand and autocontract to true in the parent section and word wrap property to true
Print Null PrintNulls Boolean If true, the numbers with 0 value will not be printed
Identifier Identifier String If you assign a identifier string, you can get the effective value of this TRpExpression from any expression inside report, so the identifier is included in the expression evaluator namespace, this is useful when working with aggregate fields and, for example, sum two aggregate values at a group footer.
Aggregate Aggregate TRpAggregate
Value Meaning
None Default behaviour
Group For each record the expression is evaluated and aggregated, the initialization is done in a group change
Page For each record the expression is evaluated and aggregated, the initialization is done in page change
General For each record the expression is evaluated and aggregated, the initialization is done in the begin of the report
Agg. Group GroupName String For Aggregate=Group indicates wich is the group that initializes the aggregate value
Agg.Type AgType TRpAggregateType
Value Meaning
Sum Sums the values
Min Get the minimum value
Max Get the maximum value
Avg Get the average of all values
Std.Desv Get the statistical standard desviation of all values
Ag.Ini.V. AgIniValue WideString

Expression with the initial value if an aggregate have been selected, note the Sum aggregate type is available to sum strings so you must place a '' value to sum the strings

P.Only One PrintOnlyOne Boolean If the value is repeated and the section have not changed, will print only once, this is usually useful to group without adding group header/footers, that is ordering the dataset and print only when the field value changes
Single line SingleLine Boolean Will force printing of text in a single line even if it contains line feeds.
F.Rotation FontRotation Angle Rotation angle in degrees for the text. Rotation in reverse clock wise, internally stored as an integer in degrees*10 scale.

Developer info

Internal component name TRpExpression
Parent class TRpGenTextComponent
Unit name rplabelitem.pas

See also Report components common text properties.