<div><%= f.label :email %><br />
<%= f.email_field :email %></div>
<div><%= f.label :password %> <i>(leave blank if you don't want to change it)</i><br />
<%= f.password_field :password, :autocomplete => "off" %></div>
比如这里的 email_field 和 password_field
现在想在默认的 user 表中加一个 nickname,但是却提示
undefined method
nickname_field' for #ActionView::Helpers::FormBuilder:0x007ff27ca73ea8`