如何在 Ruby 中正确访问和迭代多维数组？答案

【问题标题】：How do I correctly access and iterate over multidimensional arrays in Ruby?如何在 Ruby 中正确访问和迭代多维数组？
【发布时间】：2014-02-17 18:04:51
【问题描述】：

我有这段代码：

super_heroes = [
    ["Spider Man", "Peter Parker"],
    ["Deadpool", "Wade Wilson"],
    ["Wolverine", "James Howlett"]
]

super_heroes.each do |sh|
    sh.each do |heroname, realname|
        puts "#{realname} is #{heroname}"
    end
end

输出是这样的：

 is Spider Man
 is Peter Parker
 is Deadpool
 is Wade Wilson
 is Wolverine
 is James Howlett

但我想成为这样的人：

Peter Parker is Spider Man
Deadpool is Wade Wilson
Wolverine is James Howlett

在迭代代码数小时后，我仍然无法弄清楚。如果有人能把我引向正确的方向并解释我做错了什么，我将不胜感激。谢谢！

【问题讨论】：

标签： ruby arrays multidimensional-array

【解决方案1】：

如下操作：

super_heroes = [
    ["Spider Man", "Peter Parker"],
    ["Deadpool", "Wade Wilson"],
    ["Wolverine", "James Howlett"]
]

super_heroes.each do |heroname, realname|
   puts "#{realname} is #{heroname}"
end

# >> Peter Parker is Spider Man
# >> Wade Wilson is Deadpool
# >> James Howlett is Wolverine

你的代码发生了什么？

super_heroes.each do |sh| # sh is ["Spider Man", "Peter Parker"] etc..
    # here **heroname** is "Spider Man", "Peter Parker" etc.
    # every ietration with sh.each { .. } your another variable **realname**
    # is **nil**
    sh.each do |heroname, realname| 
        puts "#{realname} is #{heroname}"
        # as **realname** is always **nil**, you got the output as
        # is Spider Man
        # is Peter Parker
        # .....
        # .....
    end
end

【讨论】：

行得通！我怎么没想到！！！知道这是一个二维数组，我的灭绝告诉我可能使用 .each 方法两次。 @mdsantis：确实是“Flash”徽章。

【解决方案2】：

也试试这个，

super_heroes.each do |sh|
    puts sh.join(" is ")
end

【讨论】：