Question

我试图浏览导轨指南（http://guides.rubyonrails.org/getting_started.html），但在尝试更新图书时遇到问题： ActionController::ParameterMissing in BooksController#update

以下是图书管理员中的更新和编辑方法：

  def edit
   @book = Book.find(params[:id])
  end

  def update
   @books = Book.find(params[:id])

   if @book.update(book_params)
    redirect_to @book
   else
    render 'edit'
   end
  end

还有book_params定义：

  private
   def book_params
    params.require(:books).permit(:author, :title)
  end

这是我使用的编辑视图表单：

<%= form_for :book, url: book_path(@book), method: :patch do |f| %>

我不确定为什么会出现这个错误，因为使用基本相同的文章代码（如指南中所示）可以正常工作。

Answer 1

表单不正确，您必须在发送之前添加book密钥。

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BooksController中的ActionController :: ParameterMissing＃update param丢失或值为空

1 个答案: