自动填充Ruby on Rails中嵌套表单域的第一个实例

<%= form_for @user do |f| %>
  <%= f.text_field :name %>
  
  <%= f.fields_for :address do |address_fields| %>
    <%= address_fields.text_field :street %>
    <%= address_fields.text_field :city %>
    <%= address_fields.text_field :country %>
  <% end %>
  
  <%= f.submit %>
<% end %>

def new
  @user = User.new
  @user.build_address
end

def edit
  @user = User.find(params[:id])
end

def create
  @user = User.new(user_params)
  
  if @user.save
    # 保存成功的逻辑
  else
    # 保存失败的逻辑
  end
end

def update
  @user = User.find(params[:id])
  
  if @user.update(user_params)
    # 更新成功的逻辑
  else
    # 更新失败的逻辑
  end
end

private

def user_params
  params.require(:user).permit(:name, address_attributes: [:street, :city, :country])
end