你可以使用它，dig在浏览哈希值时也很有用

images = []
arr.each do |item|
  img = item.dig("container", "image")
  images << img unless img.nil?
end

p images

arr=[{"dag"=>{"tasks"=>[{"arguments"=>{"parameters"=>[{"name"=>"inputJson", "value"=>"{{workflow.parameters.inputJson}}"}]}, "name"=>"build-handler-workflow", "template"=>"build-handler-workflow"}]}, "name"=>"dag-build-handler-workflow"}, {"container"=>{"args"=>["{{inputs.parameters.inputJson}}"], "command"=>["cowsay"], "image"=>"docker/whalesay:latest", "resources"=>{"requests"=>{"cpu"=>"100m", "memory"=>"100Mi"}}}, "inputs"=>{"parameters"=>[{"name"=>"inputJson"}]}, "metadata"=>{"annotations"=>{"workflows.argoproj.io/progress"=>"0/10000"}}, "name"=>"build-handler-workflow", "synchronization"=>{"semaphore"=>{"configMapKeyRef"=>{"key"=>"template", "name"=>"build-handler-config"}}}}]

代码

arr.each do |hash|
  if hash['container']
    puts hash['container']['image']
  end
end

或者你可以用挖掘法

arr.each { |hash| puts hash.dig('container', 'image') if hash['container'] }

输出

docker/whalesay:latest

如果你不知道在一个给定的数组或哈希（这里是一个数组）中的哪个嵌套哈希中可以找到一个给定的键，并且想要返回一个包含整个给定对象中该键的值的数组，你可以使用下面的递归方法。

def doit(obj, key)
  case obj
  when Array
    obj.each_with_object([]) do |o, arr|
      if [Array, Hash].include?(o.class)
        res = doit(o, key)
        res.each { |v| arr << v }
      end  
    end
  when Hash
    obj.each_with_object([]) do |(k,v), arr|
      if k == key
        arr << v
      elsif [Array, Hash].include?(v.class)
        res = doit(v, key)
        res.each { |v| arr << v }
      end
    end
  end
end

doit(arr, "image")
  #=> ["docker/whalesay:latest"]

doit(arr, "name")
  #=> ["inputJson", "build-handler-workflow", "dag-build-handler-workflow",
  #    "inputJson", "build-handler-workflow", "build-handler-config"]

doit(arr[0]["dag"]["tasks"], "name")
  #=> ["inputJson", "build-handler-workflow"]

doit(arr, "inputs")
  #=> [{"parameters"=>[{"name"=>"inputJson"}]}]

非常感谢您提供所有这些替代方案，所有这些方法都很好，但我更喜欢这一个：

images = arr.filter_map { |e| e.dig("container", "image") }

我可以从数组中获取数据。