How to get specific type control with openlayers3?

Question

How to get specific type control?I have tried like below,but always got null

function getAttControl(){
   var ctrls = map.getControls();

    for (var i = 0; i < ctrls.getLength(); i++) {
        if (ctrls.get(i) instanceof ol.control.Control) {
            return ctrls.get(i);
        }
    }

    return null;
}

Answer 1

Try something like this:

  var controls = map.getControls(); // this is a ol.Collection
  controls.forEach(function(control){
    console.info(control instanceof ol.control.Zoom);
  });