Empty (Property)

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Looper, List Box, Combo Box and Table control
Chart control
Using the Empty property on a report
Empty property used in the arrays and in the associative arrays
Limits

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Empty (Property)

In french: Vide

The Empty property is used to determine if:

a Looper, Table, List Box or Combo Box control is empty. The control can be a browsing control or a memory control.
a Chart control contains no series.
a report control is empty (control linked to an item).
an array (or an associative array) contains no element.
an element of an associative array exists or not.
a queue, a list or a stack contains no element.

For a report, the Empty property is used to determine if the value of an item bound to a control has been specified for the current record.

Example

// This control becomes visible
// if the value of the item linked to the "EDT_Phone" control
// is not specified for the current record
IF EDT_Phone.Empty = False THEN
EDT_Phone.Visible = False
END

// If the "TABLE_CustomerTable" control is empty,
// add a new row into this control
IF TABLE_CustomerTable.Empty = True THEN
TableAddLine(TABLE_CustomerTable, "Davis", "Peter")
END

Syntax

<Result> = <Element used>.Empty

<Result>: Boolean

True if the specified element is empty,
False otherwise.

<Element used>: Type of element

Name of the element to be used.

Remarks

Looper, List Box, Combo Box and Table control

The Empty property is used to determine if the control is empty (the Empty property returns True).

This property applies to the Table, TreeView Table, List Box, ListView, Combo Box and Looper controls (see Limits).

Chart control

The Empty property is used to determine if the Chart control contains no series (the Empty property returns True).

Using the Empty property on a report

For a report, the Empty property is used to determine if the value of an item bound to a control has been specified for the current record.

Remark: If the value of the item linked to the specified control (for the record currently printed) corresponds to an empty string (""), this value is not considered as being empty.

Empty property used in the arrays and in the associative arrays

The Empty property is used to determine:

If an array or associative array is empty (Empty property returns True).
Example:

// Associative array of file sizes
aaFileSize is associative array of int
...
IF aaFileSize.Empty = False THEN
Info("The array contains at least one element")
END
Whether an element of an associative array exists or not. For an associative array without duplicates, the Empty property is set to False if the element exists. For an associative array with duplicates, the Empty property is set to False if at least one element exists.
Example:

// Associative array of integers
// indexed on strings and with duplicates
aaIDPerCustomer is associative array of int
// Add the identifier of customer "A"
aaIDPerCustomer["A"] = 55
// Add the identifier of customer "B"
aaIDPerCustomer["B"] = 321

IF aaIDPerCustomer["A"].Empty = False THEN
Info("At least one element A exists")
END

Limits

In the code of reports, the Empty property cannot be used on:

a report,
a report block,
a Check Box control,
a Shape control,
an Internal Report control,
an RTF control.

The Empty property can only be used on controls bound to an item (Calculated control, Bar Code, etc.).

The Empty property applies only to:

Table (and TreeView Table) controls,
List Box (and ListView) controls,
Combo Box controls,
Looper controls,
Chart controls,
Array and Associative Array variables.
Queue, List or Stack variables.

The Empty property applies only to:

Table controls,
TreeView Table controls,
List Box controls,
Combo Box controls,
Looper controls,
Chart controls,
Array and Associative Array variables,
Queue, List or Stack variables.

The Empty property applies only to:

Table controls,
TreeView Table controls,
List Box controls,
Combo Box controls,
Looper controls,
Array and Associative Array variables.

The Empty property applies only to the following elements:

List Box controls,
Combo Box controls,
Table controls,
Array and Associative Array variables,
Queue, List or Stack variables.