- List Boxes containing more than 10 000 elements
- Visibility/Invisibility of elements in a List Box or Combo Box control
- Sorted/Unsorted List Box control
- Customizing the elements found in a List Box or Combo Box control
- Tabulations: Multi-element List Box control
- Adding an element to the browser
<List Box>.Add (Function)
In french: <Liste>.Ajoute
Adds an element to:
- a List Box control populated programmatically,
- a ListView control populated programmatically,
- a Carousel control,
- a Combo Box control populated programmatically.
- To add an element at a specific position, use <List Box>.Insert.
- <List Box>.Add can be used on the single-selection and multi-selection List Box controls.
- To add an image to a standard List Box control, use gImage.
- To add elements to a Combo Box control found in a container column of a Table control, use Content.
: The element will only be added to the page displayed in the browser. For more details, see Remarks.
// Add the customer named "Moore" into "LIST_CustomerList"
<Result> = <Control to use>.Add([<Element> [, <Path of image to display>]])
- True if the element was added,
- False otherwise.
returns no result.
<Control to use>: Control name
Name of the control to be used.
<Element>: Optional character string
Element that will be added into the specified control. If this parameter is not specified, an empty row is added into the List Box or Combo Box control.
This parameter can contain:
- Carriage Return characters (CR) to add several elements.
- tabs (TAB) to obtain a multi-element List Box control (see Notes).
- gStoredValue to indicate the value that will be returned when the element is selected.
For a Carousel control
, the content of this parameter is displayed in the upper-left corner of the Carousel control.
For a ListView control,
this parameter corresponds to the image caption. This parameter can contain Carriage Return characters (CR) to add several elements. In this case:
- if <Path of image to display> is not specified, the added elements will be associated with the default image (defined in the "Details" tab of the description window of control).
- if <Path of image to display> is specified, only the first element will be added. This element will be associated with the specified image.
To add several consecutive spaces, non-breakable space characters must be used: Charact(160).
<Path of image to display>: Optional character string
Name and path of image that will be added into a ListView control. You also have the ability to use an image memo item.
This parameter is taken into account for ListView controls displayed in ListView mode only.
If this parameter is not specified, the default image (defined in the "Details" tab in the description window of control) will be used.
List Boxes containing more than 10 000 elements
The maximum number of elements in a List Box control is only limited by the available memory (theoretical maximum: 2 billion rows). Nevertheless, filling a List Box control with an important number of elements (more than 10 000) affects performance
To add many elements to a List Box control, it is recommended to use a List Box control based on a data file (i.e., a list directly linked to an HFSQL data file).
Tabulations: Multi-element List Box control
To manage the tabulations in a List Box control (for aligning columns), use the TAB
constant. For example:
LIST_Customer.Add(LastName + TAB + FirstName)
In this example, all the first names start at the same position and are aligned one under the other.
: The first call to <List Box>.Add
defines the position of tabulations. These positions will be taken as reference for all values added thereafter. Similarly, if values have been typed entered in the editor, the positions of these values are taken as reference. During the first call to <List Box>.Add
, we advise you to define the width of columns with Complete
. For example, to fix the width of columns found in "CUSTOMERS" to 10 characters:
LIST_Customer.Add(Complète(LastName, 10) + TAB + Complète(FirstName, 10))
Adding an element to the browser
When adding an element in browser code, this element is added to the page displayed in the browser only. In order for this element to be added onto the server, <List Box>.Add must be run on the server.
: In "Automatic and immediate AJAX" mode, all you have to do is switch the server process containing <List Box>.Add
to automatic AJAX mode. That's it! No additional programming is required. For more details, see AJAX
- To add elements into a Table control, use <Table>.Add.
- <List Box>.Add can be used on:
- a column of type "Combo Box" in a Table control.
- a "Table" Combo Box control.
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