当使用ruby定义一系列键时，将所有Key值作为组合字符串获取

我有以下代码

class MyClass def my_method(first,last) #this should take 2 numbers as arguments and should return the keys value(s) as a combined string end private def lines_of_code { 1 => "This is first", 2 => "This is second", 3 => "This is third", 4 => "This is fourth", 5 => "This is fifth" } end m = MyClass.new m.my_method(2,4) # This is secondThis is thirdThis is fourth" 

我应该将一个范围传递给my_method，因为inturn应该返回组合值字符串。 对不起，如果已经发布了。

提前致谢。

Answer 1

这是一个使用Hash#values_at的技巧：

 class MyClass def my_method(first, last) lines_of_code.values_at(*first..last) end private def lines_of_code { 1 => "This is first", 2 => "This is second", 3 => "This is third", 4 => "This is fourth", 5 => "This is fifth" } end end m = MyClass.new p m.my_method(2,4) # >> ["This is second", "This is third", "This is fourth"] # to get a string p m.my_method(2,4).join(" ") # >> "This is second This is third This is fourth" 

Answer 2

 lines_of_code.values_at(*first..last).join