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HTMLIFrameElement.getCanGoBack()

Non-standard
This feature is not on a current W3C standards track, but it is supported on the Firefox OS platform. Although implementations may change in the future and it is not supported widely across browsers, it is suitable for use in code dedicated to Firefox OS apps.

This API is available on Firefox OS for privileged or certified applications only.

The getCanGoBack() method of the HTMLIFrameElement interface is used to indicate whether it's possible to go back in the navigation history of the browser <iframe>.

Syntax

There is a DOMRequest version and a Promise version:

var instanceOfDOMRequest = instanceOfHTMLIframeElement.getCanGoBack();
instanceOfHTMLIframeElement.getCanGoBack().then(function(result) { ... });

Returns

Returns either

  • A DOMRequest object to handle the request's success or error. If the request is successful, the request's result will be a boolean indicating if the history can be navigated backward (true) or not (false).
  • A Promise that resolves with a boolean that equals true if the history can be navigated backward or false if not.

Parameters

None.

Example

DOMRequest:

function canMoveBwd() {
  var request = browser.getCanGoBack();

  request.onsuccess = function() {
    if (request.result) {
      back.disabled = false;
      console.log("It's possible to navigate
                   the history backward.");
    } else {
      back.disabled = true;
      console.log("It's not possible to navigate
                   the history backward.");
    }
  }
}

Promise:

function canMoveBwd() {
  browser.getCanGoBack().then(function(result) {
    if (result) {
      back.disabled = false;
      console.log("It's possible to navigate
                   the history backward.");
    } else {
      back.disabled = true;
      console.log("It's not possible to navigate
                   the history backward.");
    }
  });
}

Specification

Not part of any specification.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support Not supported Not supported Not supported Not supported Not supported
Feature Android Firefox Mobile (Gecko) Firefox OS (Gecko) IE Phone Opera Mobile Safari Mobile
Basic support Not supported Not supported 1.0.1 Not supported Not supported Not supported

Note: Use of the Browser API requires a privileged app, and browser and/or embed-apps permissions, depending on what you want to do. See Using the Browser API for more details.

See also

Document Tags and Contributors

 Contributors to this page: chrisdavidmills, wbamberg, teoli, ajaybhat, kscarfone, Jeremie
 Last updated by: chrisdavidmills,