如何使用Ajax将属性从jQuery传递到Rails

Question

I'm trying to implement a Rails 3.2 drag and drop shopping cart using jQuery ( $.ajax ).

Problem: I can't figure out how to pass my line_items controller a :product_id option in JavaScript. I believe Ajax is the key, so that's where my heads at right now. Currently, this is easily done in HTML using a button_to with embedded ruby like so:

(<%= button_to('Add to Cart', line_items_path(:product_id => product), :remote => true) %>)

However to implement the drag/drop function, the above action needs to be triggered upon a drop . How can this be done in JavaScript?

My controller:

# POST /line_items
# POST /line_items.json
def create
     @cart = current_cart
     product = Product.find(params[:product_id])
     @line_item = @cart.add_product(product.id)

     respond_to do |format|
     if @line_item.save
     format.html { redirect_to(store_index_url) }
     format.js   { @current_item = @line_item }
     format.json { render json: @line_item, status: :created, :location => @line_item }
     else
     format.html { render :action => "new" }
     format.json { render json: @line_item.errors, status: :unprocessable_entity }
    end
   end
end

My HTML:

    <% @products.each do |product| %>
     <div class="entry" data-id="<%= product.id %>">
       <h3><%= product.title %> </h3>
       <%= image_tag(product.image_url)%>
       <div style="display: none; width: 10px"><%= sanitize(product.description) %>   </div>
       <div class="price_line">
         <span class="price"><%= number_to_currency(product.price) %></span>(<%= product.unit_of_measure%>)
     <br>
     <%= button_to('Add to Cart', line_items_path(:product_id => product), :remote => true) %>
   </div>
 </div>
   <p>
<%  end %>

My Javascript:

    $(document).ready(function(){
    //End Navigation Buttons
    var dragDrop;

$('.entry').draggable({
    revert: true ,
    revertDuration: 500,
    containment: "document", 
    zIndex: 100, 
    helper: "clone",
    start: function(){
        dragDrop = $(this).data('id');
    }
});

$('#cart').droppable({
    accept: '.entry',
    activeClass: 'active',
    hoverClass: 'hovered',
    drop: function( event, ui ){
        $.post({
           url: "<%= escape_javascript(line_items_path(:product_id => product)) %>"
        });
    }
});
...

So far the drag works and the drop works except there is no :product_id passed to line_items . I just get ERROR bad URI '/store/[object Object]'. in my command console when I drop an item.

Answer 1

The post function should be:

$.post({
   url: "<%= escape_javascript(line_items_path(:product_id => product.id)) %>"
});

Note product.id instead of product