查找并替换特定的哈希值及其在数组中的值 [英] Find and replace specific hash and it's values within array

问题描述

在数组中查找特定散列并就地替换其值的最有效方法是什么，以便数组也被更改?

What is the most efficient method to find specific hash within array and replace its values in-place, so array get changed as well?

到目前为止，我已经得到了这段代码，但是在具有大量数据的实际应用程序中，这成为应用程序中最慢的部分，这可能会泄漏内存，因为当我在每个 websocket 上执行此操作时，无限内存会不断增长留言.

I've got this code so far, but in a real-world application with loads of data, this becomes the slowest part of application, which probably leaks memory, as unbounded memory grows constantly when I perform this operation on each websocket message.

array = 
  [ 
    { id: 1,
      parameters: {
        omg: "lol"
     },
     options: {
         lol: "omg"
      }
    },
    { id: 2,
      parameters: {
        omg: "double lol"
      },
      options: {
        lol: "double omg"
      }
    }
  ]

selection = array.select { |a| a[:id] == 1 }[0]
selection[:parameters][:omg] = "triple omg"
p array
# => [{:id=>1, :parameters=>{:omg=>"triple omg"}, :options=>{:lol=>"omg"}}, {:id=>2, :parameters=>{:omg=>"double lol"}, :options=>{:lol=>"double omg"}}]

推荐答案

这将在只循环一次记录后执行您的操作:

This will do what you're after looping through the records only once:

array.each { |hash| hash[:parameters][:omg] = "triple omg" if hash[:id] == 1 }

你总是可以扩展块来处理其他条件:

You could always expand the block to handle other conditions:

array.each do |hash| 
  hash[:parameters][:omg] = "triple omg" if hash[:id] == 1
  hash[:parameters][:omg] = "quadruple omg" if hash[:id] == 2
  # etc
end

而且它只会迭代元素一次.

And it'll remain iterating over the elements just the once.

也可能您更适合将数据调整为单个散列.一般来说，搜索散列比使用数组更快，特别是如果你有唯一标识符，就像这里一样.类似的东西:

It might also be you'd be better suited adjusting your data into a single hash. Generally speaking, searching a hash will be faster than using an array, particularly if you've got unique identifier as here. Something like:

{ 
  1 => {
    parameters: {
      omg: "lol"
    },
    options: {
      lol: "omg"
    }
  },
  2 => {
    parameters: {
      omg: "double lol"
    },
    options: {
      lol: "double omg"
    }
  } 
}

这样，您只需调用以下代码即可实现您的目标:

This way, you could just call the following to achieve what you're after:

hash[1][:parameters][:omg] = "triple omg"

希望有所帮助 - 让我知道您的进展情况或有任何疑问.

Hope that helps - let me know how you get on with it or if you have any questions.

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