Using DataWindow expressions as property values
When a DataWindow object property’s value can be
an expression, you can make the control’s appearance or
other properties depend on other information in the DataWindow.
A DataWindow expression can include:
-
Operators
-
The names of controls within the DataWindow, especially
column and computed field names -
DataWindow expression functions. Some functions,
such as IsRowNew, refer to characteristics of
an individual row -
User-defined functions
Different formats for the expression
When you assign an expression in the painter, you specify
just the expression:
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<span>DataWindowexpression</span> |
When you assign an expression in code, you specify a default
value, a tab, and the expression:
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<span>defaultvalue</span> [tab] <span>DataWindowexpression</span> |
Examples
In the painter
This expression for a column called emp_lname is
applied to the Background.Color property. It causes the name’s
background to be light gray (15790320) if the current row (person)
uses the day care benefit. If not, the background color is set to
white:
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If(bene_day_care = 'Y', 15790320, 1677215) |
In code
The expression assigned to the Background.Color property includes a
default value. Nested quotes complicate the syntax:
PowerBuilder
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dw_1.Object.emp_lname.Background.Color = "16777215 ~t If(bene_day_care = 'Y', 15790320, 16777215)" |
JavaScript
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dw_1.Modify("emp_lname.Background.Color = "16777215 If(bene_day_care = 'Y', 15790320, 16777215)"); |