Question

我要特别按其他阵列排列一个阵列。

EX:审议阵列

a=["one", "two", "three"]
b=["two", "one", "three"]

Now I want to sort array a in the order of b , i.e

a.each do |t|
  # It should be in the order of  b 
  puts t
end

因此,产出应当

two
one 
three

任何建议?

Answer 1

Array#sort_by is what you re after.

a.sort_by do |element|
  b.index(element)
end

3. 针对评论的更可衡量的版本:

a=["one", "two", "three"]
b=["two", "one", "three"]

lookup = {}
b.each_with_index do |item, index|
  lookup[item] = index
end

a.sort_by do |item|
  lookup.fetch(item)
end

Answer 2

如果b包括a的所有内容,如果内容是独特的,则:

puts b & a

Answer 3

假设<条码>a,就<条码>b中各项内容的顺序排列。

sorted_a = 
a.sort do |e1, e2|
  b.index(e1) <=> b.index(e2)
end

I normally use this to sort error messages in ActiveRecord in the order of appearance of fields on the form.

友情链接