數組鍵值？

Question

我將一些XML解析爲JSON，然後在http://floating-gorge-9520.herokuapp.com/currencies上提供此服務。

我想要顯示數據，以便currency的值是關鍵字，然後rate的值將成爲新貨幣數據的值。

例如：

USD: 1 
GBP: 0.5 

什麼是這樣做的最佳方式？

Answer 1

使用爲簡單起見，兩種貨幣：

require 'json' 
a = [{"currency"=>"USD", "rate"=>"1.3707"}, 
    {"currency"=>"JPY", "rate"=>"140.50"}] 
Hash[a.map { |h| [h['currency'],h['rate'].to_f] }] 

# => {"USD"=>1.3707, "JPY"=>140.5} 

上的最後一條語句只是附加一個.to_json得到JSON字符串。

Answer 2

檢查this出

require 'json' 
a = {} 
json = '[{"currency":"USD","rate":"1.3707"},{"currency":"JPY","rate":"140.50"},{"currency":"BGN","rate":"1.9558"},{"currency":"CZK","rate":"27.368"},{"currency":"DKK","rate":"7.4625"},{"currency":"GBP","rate":"0.82183"},{"currency":"HUF","rate":"311.89"},{"currency":"LTL","rate":"3.4528"},{"currency":"PLN","rate":"4.1661"},{"currency":"RON","rate":"4.5222"},{"currency":"SEK","rate":"8.9953"},{"currency":"CHF","rate":"1.2195"},{"currency":"NOK","rate":"8.3670"},{"currency":"HRK","rate":"7.6685"},{"currency":"RUB","rate":"49.0415"},{"currency":"TRY","rate":"3.0097"},{"currency":"AUD","rate":"1.5283"},{"currency":"BRL","rate":"3.2577"},{"currency":"CAD","rate":"1.5304"},{"currency":"CNY","rate":"8.3495"},{"currency":"HKD","rate":"10.6313"},{"currency":"IDR","rate":"16097.50"},{"currency":"ILS","rate":"4.8062"},{"currency":"INR","rate":"85.1580"},{"currency":"KRW","rate":"1469.53"},{"currency":"MXN","rate":"18.2348"},{"currency":"MYR","rate":"4.5158"},{"currency":"NZD","rate":"1.6558"},{"currency":"PHP","rate":"61.092"},{"currency":"SGD","rate":"1.7376"},{"currency":"THB","rate":"44.603"},{"currency":"ZAR","rate":"15.1355"}]'; 
JSON.parse(json).each { |x| a[x['currency']] = x['rate'] } 
print a