accepts_nested_attributes_for 创建重复项

Question

accepts_nested_attributes_for 创建重复项

型号

class Article < ActiveRecord::Base
  has_many :article_collections
  accepts_nested_attributes_for :article_collections, :allow_destroy => true, reject_if: :all_blank
end

class ArticleCollection < ActiveRecord::Base
  belongs_to :article
end

控制器

def update
  @article = Article.find_by_id(params[:id])
  @article.update_attributes(params[:article])
  redirect_to :index
end

参数

params = {"utf8"=>"✓"
   "article"=>
   {
    "data_id"=>"dfe9e32c-3e7c-4b33-96b6-53b123d70e7a", "name"=>"Mass", "description"=>"mass",
    "status"=>"active", "volume"=>"dfg", "issue"=>"srf", "iscode"=>"sdg", 
        "image"=>{"title"=>"", "caption"=>"",  "root_image_id"=>""},
    "article_collections_attributes"=>
    [
    {"name"=>"abcd", "type"=>"Special", "description"=>"content ","ordering_type"=>""}
    ]
  },
"commit"=>"Save", "id"=>"b8c8ad67-9b98-4705-8b01-8c3f00e55919"}

控制台

 Article.find("b8c8ad67-9b98-4705-8b01-8c3f00e55919").article_collections.count
 => 2

问题是每当我们更新文章时都会创建多个 article_collections。

假设 article_collections 是 2，这意味着如果我们正在更新文章，它会创建多个 article_collections = 4，它不会更新相同的 article_collections，而是新创建 article_collections。

为什么会创建重复项？

Answer 1

了解嵌套属性和构建。
在您的编辑操作中构建没有 article_collection.
的对象 例如@article.article_collection.build if @article.article_collection.blank?。如果它已经有一个文章集合，它不会建立一个新的对象。

Answer 2

您的参数：

params = {"utf8"=>"✓"
   "article"=>
   {
    "data_id"=>"dfe9e32c-3e7c-4b33-96b6-53b123d70e7a", "name"=>"Mass", "description"=>"mass",
    "status"=>"active", "volume"=>"dfg", "issue"=>"srf", "iscode"=>"sdg", 
        "image"=>{"title"=>"", "caption"=>"",  "root_image_id"=>""},
    "article_collections_attributes"=>
    [
    {"name"=>"abcd", "type"=>"Special", "description"=>"content ","ordering_type"=>""}
    ]
  },
"commit"=>"Save", "id"=>"b8c8ad67-9b98-4705-8b01-8c3f00e55919"}

您应该在 "article_collections_attributes" 参数中发送并允许 "id" 属性。例如，

 "article_collections_attributes"=>
    [
    {"id"=>"2", "name"=>"abcd", "type"=>"Special", "description"=>"content ","ordering_type"=>""}
    ]

我认为这段代码会对你有所帮助。