Question

Suppose I have an object @transaction that gets shown /transactions/id

def show
    @transaction = Transaction.find(params[:id]);
end

In show.html.erb, I want to have a button that when pressed changes one of the attributes of Transaction. How do I do that?

In show.html.erb, I have

<%= form_for @transaction do |t| %>
    <%= t.label :id %> : <%= @transaction.id %><br />

    <%= t.submit "pay" %>
<% end %>

EDIT: I think I may have misled with the question. The button code above generates this html:

<input id="transaction_submit" name="commit" type="submit" value="pay" />

When I click on the button, the “update” method in the controller is called. How do I pass the value from a button to a specific action in the update method? For example, suppose button1changes the transaction.name to “lalala”. How do I do this?

def update
  // if button1 is pressed, change transaction.name to lalala
  // if button2 is pressed, change transaction.amount to bobobo
end

Answer 1

Use a different form for each button:

 <%= form_for @transaction do |t| %>
     <%= t.hidden_field :name, :value=>"mike" %>
     <%= t.submit "change_name_to_mike" %>
   <% end %>

   <%= form_for @transaction do |t| %>
     <%= t.hidden_field :name, :value=>"john" %>
     <%= t.submit "change_name_to_john`" %>
   <% end %>