Question

如何更改此数组：

[["1","one"], ["2","two"], ["3","three"]]

到此？

["1","one"], ["2","two"], ["3","three"]

澄清

对于提供无效的第二版本表示歉意。这就是我真正想要的：

我想将["0","zero"]添加到[["1","one"], ["2","two"], ["3","three"]]的开头，以获取：

[["0","zero"], ["1","one"], ["2","two"], ["3","three"]]

我试过了：

["0","zero"] << [["1","one"], ["2","two"], ["3","three"]]

上面的方法产生了这个，它包含了我不想要的嵌套：

[["0","zero"], [["1","one"], ["2","two"], ["3","three"]]]

Answer 1

unshift应该为你做这件事：

a = [["1","one"], ["2","two"], ["3","three"]]
a.unshift(["0", "zero"])
=> [["0", "zero"], ["1", "one"], ["2", "two"], ["3", "three"]]

Answer 2

您可能正在寻找flatten：

返回一个新数组，该数组是此数组的一维展平（递归）。那是，对于作为数组的每个元素，将其元素提取到新数组中。如果可选的level参数确定要递展的递归级别。

[["1","one"], ["2","two"], ["3","three"]].flatten

这给了你：

=> ["1", "one", "2", "two", "3", "three"]

Answer 3

[["1","one"], ["2","two"], ["3","three"]].flatten

Answer 4

你需要让你的问题更清楚，但你的意思是以下是什么？

# Right answer
original = [["1","one"], ["2","two"]]
items_to_add = [["3","three"], ["4","four"]]
items_to_add.each do |item|
  original << item
end
original # => [["1", "one"], ["2", "two"], ["3", "three"], ["4", "four"]]

# Wrong answer
original = [["1","one"], ["2","two"]]
items_to_add = [["3","three"], ["4","four"]]
original << items_to_add # => [["1", "one"], ["2", "two"], [["3", "three"], ["4", "four"]]]

删除嵌套数组的一个级别

澄清

4 个答案: