Check if page gets reloaded or refreshed in JavaScript

Question

I want to check when someone tries to refresh a page.

For example, when I open a page nothing happens but when I refresh the page it should display an alert.

Answer 1

I found some information here Javascript Detecting Page Refresh

function UnLoadWindow() {
    return 'We strongly recommends NOT closing this window yet.'
}

window.onbeforeunload = UnLoadWindow;