Scrolltop position()

Question

I have a Javascript function that refreshes my page every 15 minutes and I’m trying to get the last position of the scroll bar before the refresh with the jQuery command.

$(window).scrollTop();

Refresh function:

var $myVar = setInterval(myTimer, 900000);

        function myTimer() {
            console.log(scrollPosition);
            loadHs();              

        }

Whenever my page is reloaded it already returns me the value zero, then I would like to rescue the last value as I scroll and set this value rescued after the refresh so that it returns to the previous position.

Answer 1

Save the position in a sessionStorage (temporary cookie that will be deleted when leaving the page) and check if it exists and is different from 0 when the page is reloaded. Then use the method window.scrollTo(x,y) to move the screen to the saved position in the cookie.

In case, you will only change the value of the axis y (vertical), leaving the x in 0:

document.addEventListener("DOMContentLoaded", function(){ // aguarda o carregamento do dom
   var pos = sessionStorage.getItem("posicao"); // atribui o cookie a uma variável
   // se a variável tiver valor, move para a posição salva no cookie
   if(+pos) window.scrollTo(0, pos);
});

var $myVar = setInterval(myTimer, 900000);

function myTimer() {
   var scrollPosition = $(window).scrollTop(); // pega a posição do scroll
   sessionStorage.setItem("posicao", scrollPosition); // salva no cookie
   loadHs();
}

Instead of sessionStorage, can use localStorage, the syntax is the same. The difference is that the second generates a permanent cookie.