Question

我需要在我的application_helper.rb中使用def，它将接受作为变量传递的模型名称。

我有一个导航视图，我试图根据$ current_opportunity的内容访问特定记录

<%# link_to "Lab", lab_path(get_id('Lab')), class: get_labs_class() %>

我试图做的是调用get_id并将'Lab'传递给它。

我的application_helper.rb有

 def get_id(model)
    model_ids = model.where("opportunity_id = ? ", $current_opportunity)
    model_ids = model_ids.first
    model_id = model_ids.id
    model_id = model_id.to_i
    return model_id
  end

如果我尝试这样跑，我会

NoMethodError in Prospects#show
Showing C:/Users/cmendla/RubymineProjects/product_development/app/views/shared/_tabs_nav.html.erb where line #61 raised:

undefined method `where' for "Lab":String
Trace of template inclusion: app/views/layouts/application.html.erb

Rails.root: C:/Users/cmendla/RubymineProjects/product_development

Application Trace | Framework Trace | Full Trace
app/helpers/application_helper.rb:25:in `get_id'
app/views/shared/_tabs_nav.html.erb:61:in `_app_views_shared__tabs_nav_html_erb__956794461_83328552'
app/views/layouts/application.html.erb:113:in `_app_views_layouts_application_html_erb___468328524_46368744'

但是，如果我将def更改为

    model_ids = Lab.where("opportunity_id = ? ", $current_opportunity)

即硬接线实验室，一切正常。

有没有办法在where语句中替换model的值？

Answer 1

尝试：

model_ids = model.constantize.where("opportunity_id = ? ", $current_opportunity)

constantize也适用于符号

Rails - 如何在控制器中为模型名称使用变量？

1 个答案: