Hi Dan

You are on the right track. When you add the property alias in the "Product property alias" Tea Commerce will auto copy that property to the order line from the Umbraco node. Now you can use the TC.GetCurrentOrder method to get the order and loop all order lines and for each find the weight property and make a sum of it.

Kind regards
Anders

I'm just trying to do this in Razor to begin with, just to get my head around it before I implement this in the base method.  I've basically changed the 'mini cart' razor macro to this:

@using TeaCommerce.Umbraco.Web
@using TeaCommerce.Api.Models
@using umbraco.MacroEngines
@inherits umbraco.MacroEngines.DynamicNodeContext

@{
    //Store id
    long storeId = long.Parse( Model._Store );

    string totalPrice = "";
    decimal totalQuantity = 0;
    decimal totalWeight = 0;
    OrderLineCollection orderLines = new OrderLineCollection();

    if ( TC.HasCurrentOrder( storeId ) ) {
        Order order = TC.GetCurrentOrder( storeId );
        totalPrice = order.SubtotalPrice.ToString();
        totalQuantity = order.OrderLines.Sum( o => o.Quantity );

        foreach ( OrderLine orderLine in order.OrderLines ) {
            totalWeight = totalWeight + orderLine.weight;
        }
    }
}
<a href="/cart/" class="items-in-cart"><span>@totalQuantity.ToString( "0.####" )</span> item(s) in cart</a>
<div class="total-amount">
    <span class="total">Total</span>
    <span class="amount">
        @(totalPrice != "" ? totalPrice : "$0.00")
    </span>
    <p>Weight: @(weight) lbs</p>
</div>

However, it's not recognising the 'weight' property on the order line:

 'TeaCommerce.Api.Models.OrderLine' does not contain a definition for 'weight' and no extension method 'weight' accepting a first argument of type 'TeaCommerce.Api.Models.OrderLine' could be found (are you missing a using directive or an assembly reference?)

 Can you see what I'm doing wrong?  I didn't think I had to grab the Umbraco node to get the property from there (that's the whole point of adding that property to the order line, right?) but maybe I do?

I should have tried this first actually, but what worked for me is: orderLine.Properties["weight"]

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