Delete (Reserved word)

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Example

Special case: the dynamic arrays

Special case: the dynamic automation objects

Special case: the class objects and the dynamic class objects

Freeing the memory space

See also

New (Reserved word)

Delete (Reserved word)

In french: Libérer

The memory occupied by a dynamic object (array, class object, ...) is automatically freed when the object is no longer used or when closing the element (window, report, ...) in which the dynamic object was declared.

Delete is used to explicitly free the memory occupied by:

The use of Delete is optional. Delete allows the developer to quickly free the available memory space.

Versions 16 and later

This feature is available for Windows Phone applications.

New in version 16

This feature is available for Windows Phone applications.

Versions 17 and later

This feature is available for iPhone/iPad applications.

New in version 17

This feature is available for iPhone/iPad applications.

Versions 18 and later

This feature is available in Windows Store apps mode.

This feature is available in Android Widget mode.

New in version 18

This feature is available in Windows Store apps mode.

This feature is available in Android Widget mode.

This feature is available in Windows Store apps mode.

This feature is available in Android Widget mode.

Versions 21 and later

This feature is available in Universal Windows 10 App mode.

This feature is available in Apple Watch mode.

New in version 21

This feature is available in Universal Windows 10 App mode.

This feature is available in Apple Watch mode.

This feature is available in Universal Windows 10 App mode.

This feature is available in Apple Watch mode.

Example

CustomerArray is dynamic array
CustomerArray = new dynamic array of 4 by 7 int
...
// Free the dynamic array
delete CustomerArray

Syntax

Delete <Name of Dynamic Object to Free>

<Name of Dynamic Object to Free>: Character string

Name of the dynamic object to free explicitly. This dynamic object can correspond to:
a dynamic array
a class object
a dynamic class object
a dynamic automation object
a dynamic structure

Remarks

Special case: the dynamic arrays

A dynamic array is automatically freed at the end of the lifetime of the variable (when the window is closed for example) or when allocating new dimensions.
If a dynamic array is declared and created in a single code line, Delete must not be used to explicitly delete the dynamic array. A runtime error will occur if Delete is used.
See Dynamic arrays for more details.

Special case: the dynamic automation objects

The dynamic automation object is automatically freed at the end of the process containing its declaration or during a new allocation of the object.

Versions 16 and later

Special case: the class objects and the dynamic class objects

To free an object, you also have the ability to use the following syntax:

<Object Name> = NULL

New in version 16

Special case: the class objects and the dynamic class objects

To free an object, you also have the ability to use the following syntax:

<Object Name> = NULL

Special case: the class objects and the dynamic class objects

To free an object, you also have the ability to use the following syntax:

<Object Name> = NULL

Freeing the memory space

You can also:

Free the memory space used by a matrix with MatDelete.
Free the memory space occupied by a matrix used by a chart with grDeleteAll.

Special case in Java/Android
The concept of destructor does not exist in Java/Android. Therefore, the code found in the destructor of a class will never be run.

An object is freed by the garbage collector when it is no longer referenced in the application. There is no way to foresee the moment when this operation occurs.

To force an object to be freed, you have the ability to assign it to NULL or to use the Free statement.