Delete

SWF Action
Action Category: 
Variables
Action Details: 
0
Action Identifier: 
58
Action Structure: 
<n.a.>
Action Length: 
0 byte(s)
Action Stack: 
pop 1 (s), pop 2 (o), push 1 (b)
Action Operation: 
s1 := pop();
o2 := pop();  // undefined or _root or _global for global variables
r := delete(s1, o2);
push(r);
Action Flash Version: 
5

Pop one string representing the name of the property to be deleted. Then pop the object from which the property is to be deleted.

In version 5 through 8, it is necessary to Push Data type undefined (0x03)1 before the string as in:

96 04 00 03 00 'a' 00 3A
delete("a");

to delete a global variable.

According to some movies I have looked at, the delete instruction returns some undefined value. In newer versions, though, the value is supposed to be a Boolean telling whether the object was really deleted (i.e. if false, then another reference is still present.)

  • 1. Since player version 9, deleting a dynamic (global) variable requires _root (or _global) instead of undefined.