popstate Redirect 1

The popstate event is fired when the active history entry changes. If the history entry being activated was created by a call to history.pushState() or was affected by a call to history.replaceState(), the popstate event's state property contains a copy of the history entry's state object.

Note that just calling history.pushState() or history.replaceState() won't trigger a popstate event. The popstate event is only triggered by doing a browser action such as a click on the back button (or calling history.back() in JavaScript).

Browsers tend to handle the popstate event differently on page load. Chrome and Safari always emit a popstate event on page load, but Firefox doesn't.

General info

Specification
HTML5
Interface
PopStateEvent
Bubbles
Yes
Cancelable
No
Target
defaultView
Default Action
None

Properties

Property Type Description
target Read only EventTarget The browsing context (<code>window</code>).
type Read only DOMString The type of event.
bubbles Read only boolean Does the event normally bubble?
cancelable Read only boolean Is it possible to cancel the event?
state Read only any The current history entry's state object (if any).

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support Yes 4.0 (2) 10.0 Yes limited
Feature Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support 3.0 (buggy in 2.2 and 2.3) 4.0 (2) 10.0 Yes limited

Example

A page at http://example.com/example.html running the following code will generate alerts as indicated:

window.onpopstate = function(event) {
  alert("location: " + document.location + ", state: " + JSON.stringify(event.state));
};
history.pushState({page: 1}, "title 1", "?page=1");
history.pushState({page: 2}, "title 2", "?page=2");
history.replaceState({page: 3}, "title 3", "?page=3");
history.back(); // alerts "location: http://example.com/example.html?page=1, state: {"page":1}"
history.back(); // alerts "location: http://example.com/example.html, state: null
history.go(2);  // alerts "location: http://example.com/example.html?page=3, state: {"page":3}

Note that even though the original history entry (for http://example.com/example.html) has no state object associated with it, a popstate event is still fired when we activate that entry after the second call to history.back().

Document Tags and Contributors

Contributors to this page: ethertank
Last updated by: ethertank,