如何在rails上传递一个从表单到jQuery脚本的参数

I have next form:

我有下一个表格:

.well
  = form_for @message, data: { chanell: @chanell }, remote: true do |f|
    .form-group
      = f.label :body, "Enter your message:"
      = f.text_area :body, rows: 3, class: 'form-control', required: true, maxlength: 2000
      %small.label.label-warning Cannot be blank or contain more than 2000 symbols.
      = hidden_field_tag 'chanell', @chanell

    = f.submit 'Send', class: 'btn btn-primary btn-lg'
.well
  = form_f