遍历哈希 目标 遍历嵌套或多维哈希。 假日供应商 指示 您可以按照季节组织各种假期的装饰品。 holiday_supplies = { :winter => { :christmas => [ "Lights" , "Wreath" ] , :new_years => [ "Party Hats" ] } , :summer => { :fourth_of_july => [ "Fireworks" , "BBQ" ] }