HTMLIFrameElement.getCanGoBack()

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

[1] Supported in chrome code only.

See also

• Using the Browser API