DESTROY
Description
Eliminates an object instance that was created with the
CREATE statement. After a DESTROY statement, properties of the deleted
object instance can no longer be referenced.
Syntax
|
1 |
DESTROY objectvariable |
|
Parameter |
Description |
|---|---|
|
objectvariable |
A variable whose datatype is a PowerBuilder |
Usage
When you are finished with an object that you created, you can call
DESTROY to release its memory. However, you should call DESTROY only if
you are sure that the object is not referenced by any other object.
PowerBuilder’s garbage collection mechanism maintains a count of
references to each object and destroys unreferenced objects
automatically.
For more information about garbage collection, see Garbage collection.
All objects are destroyed automatically when your application
terminates.
Examples
Example 1
The following statement destroys the transaction object DBTrans that
was created with a CREATE statement:
|
1 |
DESTROY DBTrans |
Example 2
This example creates an OLEStorage variable istg_prod_pic in a
window’s Open event. When the window is closed, the Close event script
destroys the object. The variable’s declaration is:
|
1 |
OLEStorage istg_prod_pic |
The window’s Open event creates an object instance and opens an OLE
storage file:
|
1 2 3 |
integer li_result istg_prod_pic = CREATE OLEStorage li_result = istg_prod_pic.Open("PICTURES.OLE") |
The window’s Close event destroys istg_prod_pic:
|
1 2 3 4 5 6 |
integer li_result li_result = istg_prod_pic.Save( ) IF li_result = 0 THEN DESTROY istg_prod_pic END IF |