Distinguish F5 Or Open For Browser

Is it possible to distinguish F5 or Open (click on link, paste URL in empty page or new tab, etc.) for Browser? Why? Because I'd like to improve ergonomics of user interface. In my

Solution 1:

In your case, using sessionStorage sounds like your best option.

Something like:

var calculatedValues = (function() {
  var savedValues = sessionStorage.getItem("values");
  if (!savedValues) {
    // Do calculationsvar values = {
      result: 10
    };

    savedValues = JSON.stringify(values);
    sessionStorage.setItem("values", savedValues);
  }
  returnJSON.parse(savedValues);
}());

sessionStorage should be unique for every window -- going to to the page under a different window will see no values and recalculate, but pressing F5 won't.

Some browsers will copy session values from one window to another when using Open in new tab on a link, but it sounds like that won't be an issue in this case.

Solution 2:

Take a look on the keydown javascript event:

https://developer.mozilla.org/en-US/docs/Web/Reference/Events/keydown

You can then use its key property to check for F5, and block the browser's reload with event.preventDefault

document.body.addEventListener("keydown", function(event) {
    if (event.key == "F5") {
        console.log("F5 Pressed!");
        //do your stuff here
        event.preventDefault();
    }
});

Fiddle: http://jsfiddle.net/ANC7e/