的Ruby / Rails - 记录添加到一个对象，每个循环迭代/对象VS阵列 [英] Ruby/Rails - Add records to an object with each loop iteration / Object vs Arrays

问题描述

我试图弄清楚如何将记录添加到现有的对象为循环的每个迭代。我有一个很难发现的对象和数组之间的区别。

我有这种

  @events = Event.find（1）
 @loops = Choices.find（：全部：上限=→5）#so环路选择模型的5个实例
 在@loops循环
       @events = Event.find（：全部：条件=＆GT; [？event.id =，loop.event_id]）
 结束
 

我想一个新的事件添加到现有@events对象，不管以何种的循环变量是编号。但是，（=）运算符仅创建@events的新实例对象。

我试过（+ =）和（小于≤）作为运营商，但得到的错误

你有一个零对象，当你没想到吧！你可能期望阵列的一个实例。在评估为零时发生错误

我试图创建一个数组

 事件= []
 事件＆LT;＆LT; Event.find（1）
 @loops = Choices.find（：全部：上限=→5）#so环路选择模型的5个实例
 在@loops循环
       事件＆LT;＆LT; Event.find（：全部：条件=＆GT;event.id =？，loop.event_id]）
 结束
 

但我不知道如何调用数组在视图中的属性。

使用的对象，我能够做的视图中创建一个循环，并调用该对象的所有属性，以及...

 ＆LT;表＆gt;
＆LT;％为@events％GT事件;
＆所述; TR＆GT;
  ＆所述; TD＆GT;＆下;％=的link_to event.title，事件％GT;＆下; / TD＆GT;
  ＆所述; TD＆GT;＆下;％= event.start_date％GT;＆下; / TD＆GT;
  ＆所述; TD＆GT;＆下;％= event.price％GT;＆下; / TD＆GT;
＆LT; / TR＆GT;
＆LT;％结束％GT;
＆LT; /表＆gt;
 

我怎么可以这样使用数​​组设置？

所以，问题是

1），请告诉我数组和对象之间的区别？结果
2）有没有一种方法来加入到每次迭代现有对象？结果
3）如果我使用一个数组，有没有办法来调用视图中为每个阵列记录的属性？

解决方案

  @events = []
@events＆LT;＆LT; Event.find（1）
@loops = Choices.find（：全部：上限=大于5）
在@loops循环
    ES = Event.find（：全部：条件=＆GT; [？event.id =，loop.event_id]）
    为电子商务在ES
        @events＆LT;＆LT; Ë
    结束
结束
 

I'm trying to figure out how to add records to an existing object for each iteration of a loop. I'm having a hard time discovering the difference between an object and an array.

I have this

 @events = Event.find(1)
 @loops = Choices.find(:all, :limit => 5)  #so loop for 5 instances of choice model
 for loop in @loops
       @events = Event.find(:all,:conditions => ["event.id = ?", loop.event_id ])
 end

I'm trying to add a new events to the existing @events object based on the id of whatever the loop variable is. But the ( = ) operator just creates a new instance of the @events object.

I tried ( += ) and ( << ) as operators but got the error

"You have a nil object when you didn't expect it! You might have expected an instance of Array. The error occurred while evaluating nil"

I tried created an array

 events = []
 events << Event.find(1)
 @loops = Choices.find(:all, :limit => 5)  #so loop for 5 instances of choice model
 for loop in @loops
       events << Event.find(:all,:conditions => ["event.id = ?", loop.event_id ])
 end

But I dont know how to call that arrays attributes within the view

With objects I was able do create a loop within the view and call all the attributes of that object as well...

<table> 
<% for event in @events %>
<tr>
  <td><%= link_to event.title, event %></td>
  <td><%= event.start_date %></td>
  <td><%= event.price %></td>
</tr>
<% end %>
</table>

How could i do this with an array set?

So the questions are

1) Whats the difference between arrays and objects?
2) Is there a way to add into the existing object for each iteration?
3) If I use an array, is there a way to call the attributes for each array record within the view?

解决方案

@events = []
@events << Event.find(1)
@loops = Choices.find(:all, :limit => 5)
for loop in @loops
    es = Event.find(:all, :conditions => ["event.id = ?", loop.event_id])
    for e in es
        @events << e
    end
end

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