De-I > delete
deleteSyntax
delete (reference
);
Arguments
reference
The name of variable or object to eliminate.
Description
Operator; destroys the object or variable specified as the reference
, and returns true
if the object was successfully deleted; otherwise returns false
. This operator is useful for freeing up memory used by scripts, although, delete
is an operator, it is typically used as a statement:
delete x;
The delete operator may fail and return false if the reference
does not exist, or may not be deleted. Predefined objects and properties, and variables declared with var
, may not be deleted.
Player
Flash 5 or later.
Example
The following example creates an object, uses it, and then deletes it once it is no longer needed:
account = new Object();
account.name = 'Jon';
account.balance = 10000;
...
delete account;
The following example deletes a property of an object:
// create the new object "account"
account = new Object();
// assign property name to the account
account.name = 'Jon';
// delete the property
delete account.name;
The following is another example of deleting an object property:
// create an Array object with length 0 array = new Array(); // Array.length is now 1 array[0] = "abc"; // add another element to the array,Array.length is now 2 array[1] = "def"; // add another element to array,Array.length is now 3 array[2] = "ghi"; // array[2] is deleted, but Array.length is not changed, delete array[2];
The following example illustrates the behavior of delete
on object references:
// create a new object, and assign the variable ref1 to refer to the object
ref1 = new Object();
ref1.name = "Jody";
// copy the reference variable into a new variable, and delete ref1
ref2 = ref1;
delete ref1;
If ref1
had not been copied into ref2
, the object would have been deleted when we deleted ref1
, because there would be no references to it. If we were to delete ref2
, there would no longer be any references to the object, and it would be destroyed and the memory it was using would be made available.
See also
var