The Window.self
read-only property returns the window itself, as a WindowProxy
. It can be used with dot notation on a window
object (that is, window.self
) or standalone (self
). The advantage of the standalone notation is that a similar notation exists for non-window contexts, such as in Web Workers. By using self
, you can refer to the global scope in a way that will work not only in a window context (self
will resolve to window.self
) but also in a worker context (self
will then resolve to WorkerGlobalScope.self
).
Example
Uses of window.self
like the following could just as well be replaced by window
.
if (window.parent.frames[0] != window.self) { // this window is not the first frame in the list }
Furthermore, when executing in the active document of a browsing context, window
is a reference to the current global object and thus all of the following are equivalent:
var w1 = window; var w2 = self; var w3 = window.window; var w4 = window.self; // w1, w2, w3, w4 all strictly equal, but only w2 will function in workers
Specifications
Specification | Status | Comment |
---|---|---|
HTML Living Standard The definition of 'Window.self' in that specification. |
Living Standard | No difference from the latest snapshot HTML 5.1 |
HTML 5.1 The definition of 'Window.self' in that specification. |
Recommendation | No difference from the HTML5 |
HTML5 The definition of 'Window.self' in that specification. |
Recommendation | First snapshot containing the definition of Window.self . |
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
self | Chrome Full support Yes | Edge Full support 12 | Firefox Full support Yes | IE Full support Yes | Opera Full support Yes | Safari Full support Yes | WebView Android Full support Yes | Chrome Android Full support Yes | Firefox Android Full support Yes | Opera Android Full support Yes | Safari iOS Full support Yes | Samsung Internet Android Full support Yes |
Legend
- Full support
- Full support
See also
- Its
Worker
equivalent,WorkerGlobalScope.self
.