How to notify the user about data loss in case of reloading the page without saving?

Question

I have a react redax application, and after I save a new object of tabs in redax, I need the user to receive a notification if he wants to refresh the page, saying that you really want to refresh the page without saving, in which case you upload the changes and if it clicks cancel reboot is not done, how can I implement thi

Answer 1

the window.onbeforeunload javascript API provides an attribute which you can asign a function:

window.onbeforeunload = () => {
  // Add internal app logic here
};