Shopify post Ajax add to cart success message on C

I'm building an online store using Shopify and have come across some jQuery/Ajax code in the default template that I would like to modify for my needs.

function addToCartSuccess (jqXHR, textStatus, errorThrown){

  $.ajax({
    type: 'GET',
    url: '/cart.js',
    async: false,
    cache: false,
    dataType: 'json',
    success: updateCartDesc
  });
  window.location = "/cart";
  $('.add-cart-msg').hide().addClass('success').html('Item added to cart! <a href="/cart" title="view cart">View cart and check out &raquo;</a>').fadeIn('300');
}

I added the window.location line myself thinking it would post the message on the Cart page but to no avail. If I remove that code the success message is posted on the product page when the Add to Cart button is pressed so it does actual work without modification.

I also tried creating my own function with a POST command but really I am best guessing as I don't have any previous experience with this level of jQuery/Ajax

function updateCartDesc (jqXHR, textStatus, errorThrown){

  $.ajax({
    type: 'POST',
    url: '/cart',
    async: false,
    cache: false,
    dataType: 'html',
    success: function (){('.add-cart-msg').hide().addClass('success').html('Item added to cart! <a href="/cart" title="view cart">View cart and check out &raquo;</a>').fadeIn('300');
    }
});

Any pointers on where I am going wrong? Tutorials, guides etc. would be wonderful. Thanks

You are going to have to redirect the user to the cart page with a param in the URL that tells the cart page to show a message. Something like the below:

Your Ajax add to cart call and callback

$.ajax({
    type: 'GET',
    url: '/cart.js',
    async: false,
    cache: false,
    dataType: 'json',
    success: updateCartDesc
});

var updateCartDesc = function() {
    //redirect the user to the cart and pass showSuccess=true in the URL
    window.location = "/cart?showSuccess=true";
};

Script on your cart page

$(function() {
    //if the current URL contains showSuccess,
    //display the success message to the user
    if(window.location.href.indexOf('showSuccess') != -1) {
        $('.add-cart-msg').hide()
                          .addClass('success')
                          .html('Item added to cart!')
                          .fadeIn('300');

    }
});

Just to note that this code assumes you have an element on the /cart page with class add-cart-msg.