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select box height - This property is used to convert the select box to a List Box and displays the choices in a selectable list instead of the dropdown box.
multiple - This specifies that multiple values can be selected from the select box. The default value of the property is 'false'. If set to 'true' the select box will convert to a List Box.
Choices / Choice Values Properties
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For Rich Display Files the choices parameter values would ususlly usually be bound to a field allowing dynamic SQL selection.
To find more information on the choice selection criteria and choices parameter properties, view the Parameter Markers section here.
Blank Option
The blank option property allows you to provide a option containing blank text before any other choices from the database file are displayed.
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If you are unable to get any information to display on your choice URL script you can use the showErrors() API to try and debug the reason the results are unable to display.
showErrors() API Documentation
Example of the showErrors() API displaying JSON error response example:
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