Generate dynamic link with angularjs

Question

Please help me, I have this function in my main controller:

$scope.link = function (demo) {
            var index = $scope.demos.findIndex((v) => v.id === demo.id)
            alert(index)
        }

instead of making an alert with the index, I would like it to take me to a link, example:

if (index % 2 == 0) {
           take me to a link...'www.example.com'     
            }

how can i do this?