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将1哈希的内容添加到另一哈希中

ruby-on-rails-4 ruby ruby-on-rails

Dhaval Chheda · 技术社区 · 6 年前

我有一个父散列,它会发生变化,我想确保子散列接受这些变化,但同时保留以前的密钥,这些密钥不会丢失

这些是我的样本

one = {"endpoints"=>["get_route"], "features"=>["channel_selection"], "get_route"=>{"output"=>["total_length", "seca_length"], "options"=>["panama", "abcd"]}}

other = {"endpoints"=>["get_route"], "features"=>["channel_selection"], "get_route"=>{"output"=>["total_length", "seca_length"], "options"=>["panama", "suez", "kiel"]}}

我要另一个杂碎看起来像

other = {"endpoints"=>["get_route"], "features"=>["channel_selection"], "get_route"=>{"output"=>["total_length", "seca_length"], "options"=>["panama", "abcd", suez", "kiel"]}}

我试过下面的代码,但它不起作用

result = propogate_changes(one, other)

def propogate_changes(one, other)
    one_keys = one.keys
    other_keys = other.keys
    combined = Hash.new
    unique_keys = one_keys.concat(other_keys).uniq

    unique_keys.each do |key|
        if(one[key].is_a?(Array)) then
            # if(other[key] == nil) then
            #     combined[key] = one[key]
            # else
                combined[key] = one[key].concat(other[key]).uniq
            # end
        else
            combined[key] = add_allowance(one[key], other[key])
        end
    end
    return combined
end

当一个密钥存在于一个密钥中,而另一个密钥丢失时,上述代码将失败

我也试过了 merge, deep_merge, reverse_merge 但它们都用一个散列覆盖了我的另一个散列,但没有一个保留原始数据。

如对此有任何建议,我们将不胜感激。

1 回复 | 直到 6 年前

Jignesh Gohel 6 年前

试试这个自定义合并逻辑。

def find_missing_items_in_arr(arr1, arr2)
  arr1_size = arr1.size
  arr2_size = arr2.size

  if (arr1_size == arr2_size) && (arr1 & arr2).size == arr1_size
    return [] # Same array
  end

  arr2 - arr1
end

def custom_merge(target_hash, source_hash)
  # If you want to preserve frozen state of entries, please use `clone`
  duped_target_hash = target_hash.dup

  source_hash.each do |k, v|
    unless duped_target_hash.key?(k)
      duped_target_hash[k] = v
      next
    end

    case v
      when Array
        missing_items_in_arr = find_missing_items_in_arr(duped_target_hash[k], v)
        if missing_items_in_arr.size > 0
          duped_target_hash[k] += missing_items_in_arr
        end
      when Hash
        duped_target_hash[k] = custom_merge(duped_target_hash[k], v)
      else
        # Nothing to do here
    end
  end

  duped_target_hash
end

用法

one = {
  "endpoints"=>["get_route"],
  "features"=>["channel_selection"],
  "get_route"=> {
    "output"=> ["total_length", "seca_length"],
    "options"=> ["panama", "abcd"]
  }
}

other = {
  "endpoints"=>["get_route"],
  "features"=>["channel_selection"],
  "get_route"=> {
    "output"=> ["total_length", "seca_length"],
    "options"=> ["panama", "suez", "kiel"]
  }
}

rs_hash = custom_merge(other, one)

puts rs_hash

注意 :rails提供 deep_merge 但这可以在铁轨外使用。我已经测试过了,它会返回你想要的输出。它还处理更多的嵌套条目,如

one = {
  "endpoints"=>["get_route"],
  "features"=>["channel_selection"],
  "get_route"=> {
    "output"=> ["total_length", "seca_length"],
    "options"=> ["panama", "abcd"],

    "custom_options" => {
      "custom_output" => ["abc"],
      "custom_input" => ["xyz" ]
    }
  }
}

other = {
  "endpoints"=>["get_route"],
  "features"=>["channel_selection"],
  "get_route"=> {
    "output"=> ["total_length", "seca_length"],
    "options"=> ["panama", "suez", "kiel"],

    "custom_options" => {
      "custom_output" => ["abc", "def"]
    }
  }
}

希望这有帮助。