[ruby-on-rails] Ruby on Rails form_for select field with class

I am beating my head against the wall on this one. I want to make a simple select tag using the f.select tag but nothing I do works. I put an example below:

<%= f.select(:object_field, ['Item 1', 'Item 2', 'Item 3', 'Item 4', 'Item 4'], :class => 'my_style_class')%>

Ok, so basically it is a simple list that once the form is submitted it places the value into the object_field. That all works, but viewing the page source the class tag is not included. It doesn't throw an error, it just skips it all together.

If anyone has any suggestions I would greatly appreciate it.

You can see in here: http://apidock.com/rails/ActionView/Helpers/FormBuilder/select

Or here: http://apidock.com/rails/ActionView/Helpers/FormOptionsHelper/select

Select tag has maximun 4 agrument, and last agrument is html option, it mean you can put class, require, selection option in here.

= f.select :sms_category_id, @sms_category_collect, {}, {class: 'form-control', required: true, selected: @set}

You can also add prompt option like this.

<%= f.select(:object_field, ['Item 1', 'Item 2'], {include_blank: "Select something"}, { :class => 'my_style_class' }) %>

This work for me

<%= f.select :status, [["Single", "single"], ["Married", "married"], ["Engaged", "engaged"], ["In a Relationship", "relationship"]], {}, {class: "form-control"} %>