onclick刷新页面后进行更改

Question

I have this submit button calling onBeforeEventRender function
<input type="submit" value="Sumbit" name="submit" onclick="onBeforeEventRender();" />

function:

dp.onBeforeEventRender = function(args) {
    var start = new DayPilot.Date(args.e.start);
    var end = new DayPilot.Date(args.e.end);
    var today = new DayPilot.Date().getDatePart();
    var now = new DayPilot.Date();
    var job = args.e.job;
    var barColor = "#aaaaaa";
    var input = document.getElementById("port").value;


    if (args.e.port == input) {
        args.e.backColor = 'green';
    } else if (args.e.port !== input && args.e.active == 1) {
        args.e.backColor = 'red';
    }
};

Main var is var input = document.getElementById("port").value; which is getting value from my searchbox. When I press submit button nothing changed, but after page refresh, cells with port == input will changed their backColor. Why is this happening after refresh? Or is there anything which makes my button do onClick function and refresh page automatically?

Thank you ;)