How do I call a piece of JavaScript in Ember?

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C#

ASP.NET

Hey guys, I really didn't know how to explain myself better in the title, but what I want is to be able to make a code that for example when choosing 2 dates on a form are checked immediately if one is before the other and if not then it sends an alert... I know how to do the code I just don't know how to call it in ember

UPDATE:

$(document).ready(function () {
    var event = new Date();
    var arrival = new Date();
    var departure = new Date();
    var departureFlight = new Date();
    var returnFlight = new Date();

    event = $('#inputEventStart').data('date');
    arrival = $('#inputArrival').data('date');
    departure = $('#inputDeparture').data('date');
    departureFlight = $('#inputFlDeparture').data('date');
    returnFlight = $('#inputFlReturn').data('date');

    if (arrival < event) {
        alert("Arrival date must be after the event!");
        sender._textbox.set_Value('');
    }
    if (departure > event) {
        alert("Departure date must be before the event!");
        sender._textbox.set_Value('');
    }
    if (returnFlight < departureFlight) {
        alert("Return flight must be after flight departure");
        sender._textbox.set_Value('')
    }
});

I have this code, what happens is it will only work if I refresh browser and I want it to work without having to refresh it