Question

我的代码存在问题。

这是控制器：

def create 
  @mean = TrasmissionMean.new(trasmission_mean_params)
  if @mean.save
    flash[:success] = "Mezzo di Trasmissione #{@mean.description}"
  else
    flash[:error] = "Error #{@mean.errors.full_messages}"
    render :action => 'new'
  end
end

def trasmission_mean_params 
  params.require(:mean).permit(:description)
end

我的代码存在问题。

这是视图，渲染形式为：

<div class="row">
  <div class="col-md-10 col-md-offset-1">
    <%= form_for @mean, :html => {:class => "form-horizontal" },:url => url_for(:controller => "trasmission_means", :action => "create" ) do |f| %>
      <hr>
      <%= render partial: "form", :locals => { :@mean => @mean, :f => f } %>
      <hr>
      <%= f.submit "Aggiungi", class: 'btn btn-success btn-lg pull-right' %>
   <% end %> 
  </div>
</div>

渲染形式：

<div class="form-group">
  <div class="col-lg-12">
    <%= f.text_area :description, :rows => 4, class: 'form-control ', placeholder: 'Descrizione' %>
  </div>
</div>

这是错误。我不明白问题出在哪里

ActionController::ParameterMissing in Protocol::TrasmissionMeansController#create param缺失或值为空：mean

Answer 1

参数基于类

def trasmission_mean_params 
  params.require(:mean).permit(:description)
end

在params散列中寻找均值但是你的类被称为TransmissionMean，这意味着它应该是

def trasmission_mean_params 
  params.require(:transmission_mean).permit(:description)
end

Protocol :: TrasmissionMeansController中的ActionController :: ParameterMissing #create

1 个答案: