Question

我正在使用Rails 4制作应用。我使用简单的表格形式。

我正在制作演示者，在表单输入上显示略有不同的标签。

我按照以下方式使用它们：

表格形式：

<%= f.input :description, :as => :text, :label => " <%= @project_presenter.description %> ", :input_html => {:rows => 10} %>

在演示者中：

class ProjectPresenter

    def initialize(project, profile)
        @project = project
        @profile = user.profile
    end

    def description

        if student?
            "What does the project involve? "
        elsif sponsor?
            "Describe the project. "
        elsif educator?
            "What does the project involve? How will students be involved in the project? "
        elsif researcher?
            "What's involved in the project? Describe the issues to be addressed."
        end
    end

当我尝试这个时，我收到指向此行的语法错误：

<%= f.input :description, :as => :text, :label => " <%= @project_presenter.description %> ", :input_html => {:rows => 10} %>

我认为它不希望＆lt;％=％＆gt;演示者周围的标签。

如何在表单中使用演示者？

Presenter定义为：

class ProjectPresenter

    def initialize(project, profile)
        @project = project
        @profile = user.profile
    end

    def description
    ....
    end

用户模型中的关联是：

  has_many :articles
  has_many :authentications, :dependent => :delete_all

  has_many :comments

  belongs_to :organisation
  has_one :profile
  has_many :qualifications
  has_many :identities

  has_many :trl_assessments, as: :addressable

  has_and_belongs_to_many :projects

Answer 1

我不熟悉演示者，但有一件事我可以注意到description类中的Presenter方法出错：你没有正确关闭字符串。

def description
  if student?
    "What does the project involve?"
  elsif sponsor?
    "Describe the project." 
  elsif educator?
    "What does the project involve? How will students be involved in the project? "
  elsif researcher?
    "What's involved in the project? Describe the issues to be addressed."
  end
end

而不是你现在拥有的东西：

def description
  if student?
    "What does the project involve? 
  elsif sponsor?
    "Describe the project. 
  elsif educator?
    "What does the project involve? How will students be involved in the project? "
  elsif researcher?
    "What's involved in the project? Describe the issues to be addressed."
  end
end

此外，在您看来：

<%= f.input :description, :as => :text, :label => " <%= @project_presenter.description %> ", :input_html => {:rows => 10} %>

由于您已在@project_presenter.description代码中调用erb，因此您无需在此处指定其他<%= %>。如果你想在这里实现的是字符串插值，你所要做的就是把它称为："#{@project_presenter.description}"

<%= f.input :description, :as => :text, :label => "#{@project_presenter.description}", :input_html => {:rows => 10} %>

与此同时，我认为您应该能够直接致电@project_presenter.description而不进行插值，如下所示：

<%= f.input :description, :as => :text, :label => @project_presenter.description, :input_html => {:rows => 10} %>

Rails - 在表单中使用演示者

1 个答案: