jquery pagination scroll to top

Question

I am using the attached code for pagination, im trying to add a function to scroll the page to the top when navigating the pagination. My source script is below, that i found here.

    $(document).ready(function () {

        //how much items per page to show
        var show_per_page = 5;
        //getting the amount of elements inside content div
        var number_of_items = $('#content').children().size();
        //calculate the number of pages we are going to have
        var number_of_pages = Math.ceil(number_of_items / show_per_page);

        //set the value of our hidden input fields
        $('#current_page').val(0);
        $('#show_per_page').val(show_per_page);
        var navigation_html = '<ul>';

        navigation_html += '<li class="previous_link">';
        navigation_html += '<a href="javascript:previous();">&larr;</a>';
        navigation_html += '</li>';
        var current_link = 0;
        while (number_of_pages > current_link) {
            navigation_html += '<li class="page_link" id="id' + current_link + '">';
            navigation_html += '<a href="javascript:go_to_page(' + current_link + ')" longdesc="' + current_link + '">' + (current_link + 1) + '</a>';
            current_link++;
            navigation_html += '</li>';
        }
        navigation_html += '<li>';
        navigation_html += '<a class="next_link" href="javascript:next();">&rarr;</a>';
        navigation_html += '</li>';
        navigation_html += '</ul>';

        $('#page_navigation').html(navigation_html);


        //add active class to the first page link
        $('#page_navigation .page_link:first').addClass('active');

        //hide all the elements inside content div
        $('#content').children().css('display', 'none');

        //and show the first n (show_per_page) elements
        $('#content').children().slice(0, show_per_page).css('display', 'block');

    });

function previous() {

    new_page = parseInt($('#current_page').val()) - 1;
    //if there is an item before the current active link run the function
    if ($('.active').prev('.page_link').length == true) {
        go_to_page(new_page);
    }

}

function next() {
    new_page = parseInt($('#current_page').val()) + 1;
    //if there is an item after the current active link run the function
    if ($('.active').next('.page_link').length == true) {
        go_to_page(new_page);
    }


}

function go_to_page(page_num) {
    //get the number of items shown per page
    var show_per_page = parseInt($('#show_per_page').val());

    //get the element number where to start the slice from
    start_from = page_num * show_per_page;

    //get the element number where to end the slice
    end_on = start_from + show_per_page;

    activate_id = page_num;
    var get_box = document.getElementById("id" + page_num);
    //hide all children elements of content div, get specific items and show them
    $('#content').children().css('display', 'none').slice(start_from, end_on).css('display', 'block');

    /*get the page link that has longdesc attribute of the current page and add active class to it
     and remove that class from previously active page link*/
    $("#page_navigation").find('li.active').removeClass("active");
    $(get_box).addClass("active");

    //update the current page input field
    $('#current_page').val(page_num);
}

I have tried adding

$('#page_navigation .page_link').click(function () {
        $('body,html').animate({
            scrollTop: 0
        }, 600);
        return false;
    });

This is unfamiliar territory for me so any assistance would be much appreciated.

Answer 1

As both previous() and next() seem to use the go_to_page() function for navigation, it seems like the easiest way would be to add:

$('body,html').animate({
    scrollTop: 0
}, 600);

at the end of the go_to_page() function. That way the animation will occur after the content has switched, no matter if the user page forward or backward.

Something like this:

function go_to_page(page_num) {

    // ... code removed for simplicity ...    

    //update the current page input field
    $('#current_page').val(page_num);

    // Scroll to the top
    $('body,html').animate({
        scrollTop: 0
    }, 600);
}