Question

name: {
        "accounts"=>{
          "data"=>[

              {
              "access_token"=>"CAAUCR7n0ZC50BAGmqTb3FEYz9FzZCZAZBFdVZC6AM3iQrGUsVqWvCfI5q5vh4seRH6LwIQTSkZAznzeBaPlZBjQ3zcwdfWxPBIr78FZBVa8pymUzVX0UESSS7QC0Dm7iIUCMyRH175HV6ZCa2ugBmbJNB7joZB7oiILPH5jtpcCLkg8e7ztxyjeSODSO4ZBAM9z1pkZD",
              "name"=>"UNX",
              "id"=>"387832931391777",
              },
              {
              "access_token"=>"CAAUCR7n0ZC50BAEYnXR7bWGvhktsGXCaB43vB0mhSuKgZBQG1m5FyovssyVKt0XYv7K7essxPkVPU3nQZCqrQJeTtWhApV1cSYGsb4JbNmYlUiHmLHueEBjuomqRWVX6tvMZA0dA5zqMApbmPUtA7SBqruWUFzZAwZC9xZBXFMZCZAW7WNEL7epkb9dmiL2pX3AoZD",
              "name"=>"Fuitter",
              "id"=>"1412081982453898",
              }
              ]}}

我正在尝试从name哈希数组中获取data键。我已经使用each循环，但这样我必须在循环内嵌套循环。有没有其他方法可以使这项工作？

这个name键实际上是数据类型为json的数据库中的列。

<% session[:user].account.name.each do |test| %>
  <% test.each do |me| %>
    <%= me['data']['name']%> #unable to fetch name and gives me undefined method `[]' for nil:NilClass error 
    <br>
  <% end %>
<% end %>

我试图通过嵌套循环来获取值，但是我收到了这个错误

unable to fetch name and gives me undefined method `[]' for nil:NilClass error

Answer 1

这样做：

data_hash = { name: {
        "accounts"=>{
          "data"=>[

              {
              "access_token"=>"CAAUCR7n0ZC50BAGmqTb3FEYz9FzZCZAZBFdVZC6AM3iQrGUsVqWvCfI5q5vh4seRH6LwIQTSkZAznzeBaPlZBjQ3zcwdfWxPBIr78FZBVa8pymUzVX0UESSS7QC0Dm7iIUCMyRH175HV6ZCa2ugBmbJNB7joZB7oiILPH5jtpcCLkg8e7ztxyjeSODSO4ZBAM9z1pkZD",
              "name"=>"UNX",
              "id"=>"387832931391777",
              },
              {
              "access_token"=>"CAAUCR7n0ZC50BAEYnXR7bWGvhktsGXCaB43vB0mhSuKgZBQG1m5FyovssyVKt0XYv7K7essxPkVPU3nQZCqrQJeTtWhApV1cSYGsb4JbNmYlUiHmLHueEBjuomqRWVX6tvMZA0dA5zqMApbmPUtA7SBqruWUFzZAwZC9xZBXFMZCZAW7WNEL7epkb9dmiL2pX3AoZD",
              "name"=>"Fuitter",
              "id"=>"1412081982453898",
              }
              ]
          }
        }
      }

data_hash[:name]['accounts']['data'].map { |d| puts d['name'] }
    # => UNX
    # => Fuitter

循环遍历哈希数组

1 个答案: