Question

I’m displaying a list of items which have a priceattribute in an HTML table.

What is the right way of getting the total price add the end of the table (and where should the calculation happen)?

I can think of 3 obvious ways, but I don’t know which one is the most “orthodoxic”

1- in the controller

@items = Item.all
@item_total = @items.sum(:price)

and I simply display @item_totalin my last line

2- in the view, on the last line

<%= @items.sum(:price) %>

But I’m not sure that it’s OK to do this in a view (it works, but is it OK?)

3- in the view, add this on the last line

<%= @items.inject(0){|s, e| s + e.price} %>

But this doesn’t feel right to add this kind of logic in the view.

So which one of these is the right one? Or is there another way I’m missing?

Answer 1

try this way

# In your controller write
@item_total = Item.sum(:price)

and @item_total use in your view file

Update

If you use this like index action then you can do this way

@items = Item.all
@item_total = @items.sum(:price)

but if you want to only item_total then don’t pass two queries for sum you can do like

@item_total = Item.sum(:price)