Question

I want to dynamically set the url path of a

  - application_path = @object.class.name.underscore + "_path"
  = link_to "<input type='button' value='Cancel' class ='bigbutton go_back'/>".html_safe, application_path(@application)

but i keep getting

 undefined method `application_path' for #<#<Class:0x00000103d11d80>:0x00000103d04a68>

any ideas on how to achieve this behavior

Answer 1

In the general case, you can use Object#send to call a method based on a symbol (which you can get from a string using to_sym):

send(application_path.to_sym, @application)

From the docs:

send(symbol [, args…]) → obj

Invokes the method identified by symbol, passing it any arguments specified.

But in this case, because your dynamic string is simple enough, Rails has a built-in method to do this, url_for:

url_for(@application)

Example from the docs:

<%= url_for(@workshop) %>
# calls @workshop.to_param which by default returns the id
# => /workshops/5

Note: this is assuming your @application is a model object where the route matches the model name. In your code there seems to be two instance variables, @object and @application, but you haven’t explained them fully, so you may need to modify the above to pass in @object instead of @application.