In Ruby 1.9.x I have a hash that maintains its order
在Ruby 1.9.x中，我有一个维护其顺序的哈希
hsh = {9=>2, 8=>3, 5=>2, 4=>2, 2=>1}
Is there a way to get say the key of the third element other than this:
有没有办法说出除此之外的第三个元素的关键：
hsh.to_a[2][0]
2 个解决方案
#1
19
Try using Hash#keys and Hash#values:
尝试使用Hash＃keys和Hash＃值：
thirdKey = hsh.keys[2]
thirdValue = hsh.values[2]
#2
2
Why do you use hash instead of an array? The array fits perfect for ordered collections.
为什么使用哈希而不是数组？该阵列非常适合有序集合。
array = [[9, 2], [8, 3], [5, 2], [4, 2], [2, 1]]
array.each { |pair| puts pair.first }
Sorting of arrays is very simple, ultimately.
最终，对数组进行排序非常简单。
disordered_array = [[4,2], [9,2], [8,3], [2,1], [5,2]]
disordered_array.sort { |a,b| b <=> a }
=> [[9, 2], [8, 3], [5, 2], [4, 2], [2, 1]]
Correct me if I'm wrong.
如我错了请纠正我。
#1
19
Try using Hash#keys and Hash#values:
尝试使用Hash＃keys和Hash＃值：
thirdKey = hsh.keys[2]
thirdValue = hsh.values[2]
#2
2
Why do you use hash instead of an array? The array fits perfect for ordered collections.
为什么使用哈希而不是数组？该阵列非常适合有序集合。
array = [[9, 2], [8, 3], [5, 2], [4, 2], [2, 1]]
array.each { |pair| puts pair.first }
Sorting of arrays is very simple, ultimately.
最终，对数组进行排序非常简单。
disordered_array = [[4,2], [9,2], [8,3], [2,1], [5,2]]
disordered_array.sort { |a,b| b <=> a }
=> [[9, 2], [8, 3], [5, 2], [4, 2], [2, 1]]
Correct me if I'm wrong.
如我错了请纠正我。