Question

我有一个名为actors的数组，其中包含对象，每个对象都有关于一个演员的数据，例如他的名字等。

我试图通过Rails将数据保存在我的SQLite数据库中，但是我遇到了一些问题。

我在actor控制器中尝试了几个创建函数，

def create
  actors = Actor.create(params[:actors])
  redirect_to :root
end

这会创建一条新记录，但内容为emtpy，

{"id":8,"name":null,"character":null,"movie_id":null}

我想也许我需要在create函数中添加参数，如此，

def create
  actors = Actor.create(params[:actors], movie_id: params[:movie_id], name: params[:name], character: params[:character])
  redirect_to :root
end

但是这会返回错误

ArgumentError（参数数量错误（0..1为2））

*更新*

这是来自帖子请求的rails日志，

Started POST "/actors.json" for 127.0.0.1 at 2016-01-12 17:08:05 +0100
Processing by ActorsController#create as JSON
  Parameters: {"_json"=>[{"name"=>"Michael B. Jordan", "character"=>"Adonis Creed", "movie_id"=>312221}, {"name"=>"Sylvester Stallone", "character"=>"Rocky Balboa", "movie_id"=>312221}, {"name"=>"Graham McTavish", "character"=>"Tommy Holiday", "movie_id"=>312221}, {"name"=>"Tessa Thompson", "character"=>"Bianca", "movie_id"=>312221}, {"name"=>"Phylicia Rashād", "character"=>"Mary Anne Creed", "movie_id"=>312221}, {"name"=>"Hans Marrero", "character"=>"Flores", "movie_id"=>312221}, {"name"=>"Will Blagrove", "character"=>"James", "movie_id"=>312221}, {"name"=>"Tony Bellew", "character"=>"'Pretty' Ricky Conlan", "movie_id"=>312221}, {"name"=>"Ritchie Coster", "character"=>"Pete Sporino", "movie_id"=>312221}, {"name"=>"Jacob 'Stitch' Duran", "character"=>"Stitch", "movie_id"=>312221}, {"name"=>"Malik Bazille", "character"=>"Amir", "movie_id"=>312221}, {"name"=>"Wood Harris", "character"=>"Tony 'Little Duke' Burton", "movie_id"=>312221}, {"name"=>"Gabe Rosado", "character"=>"Leo 'The Lion' Sporino", "movie_id"=>312221}], "actor"=>{}}
  User Load (0.2ms)  SELECT  "users".* FROM "users" WHERE "users"."id" = ?  ORDER BY "users"."id" ASC LIMIT 1  [["id", 1]]
Completed 500 Internal Server Error in 6ms (ActiveRecord: 0.2ms)

Answer 1

您需要迭代params [：actors]哈希中的每个actor，并将其中每个参数的值分配给您的Actor模型。

def create
  actors = params[:actors].each do |key, value|
      Actor.create({
        movie_id: value[:movie_id], 
        name: value[:name],
        character: value[:character]
      })
  end
  redirect_to :root
end

免责声明：我怀疑这段代码是100％正确的，我不确定我是否正确地使用了语法来获取参数的值（这有助于查看参数是什么），但这应该会让你进入正确的方向。还可以尝试查看这些帖子：

Accessing array of parameters inside the params[] value

Build array of objects from params hash after Transaction block fails, Rails

编辑：试试这个......

def create
  actors = params[:json].each do |actor|
      Actor.create({
        movie_id: actor["movie_id"], 
        name: actor["name"],
        character: actor["character"]
      })
  end
  redirect_to :root
end

Answer 2

您需要将哈希值传递给create方法。

执行以下操作：

迭代params[:actors]
中的每个对象
```
params[:actors].each do |actor|
```

通过从对象中提取值，使用值name，character和movie_id创建以下哈希值。

hsh = {
  :name => actor.name,   #Assuming your actor object has this property
  :character => actor.character,  #Similarly actor.character
  :movie_id => actor.movie_id     #actor.movie_id
}

现在您可以将其传递给create，如：
```
Actor.create(hsh)
```

修改
看到您的错误日志后，您似乎需要遍历params[:_json]数组。

所以你可以这样做：

params[:_json].each do |actor| Actor.create(actor) end

这应该有效，因为params[:_json]中的每个json文档都是一个actor哈希。

ArgumentError（创建多个记录时参数数量错误

2 个答案: