ruby 1.9如何将数组转换成没有括号的字符串

My question is about how to convert array elements to string in ruby 1.9 without getting the brackets and quotation marks. I've got an array (DB extract), from which I want to use to create a periodic report.

我的问题是如何在ruby 1.9中将数组元素转换成字符串而不需要括号和引号。我有一个数组(DB解压)，我想用它来创建一个定期报告。

myArray = ["Apple", "Pear", "Banana", "2", "15", "12"]

In ruby 1.8 I had the following line

在ruby 1.8中，我有以下一行

reportStr = "In the first quarter we sold " + myArray[3].to_s + " " + myArray[0].to_s + "(s)."
puts reportStr

Which produced the (wanted) output

哪个产生了(想要的)输出

In the first quarter we sold 2 Apple(s).

第一季度我们卖出了两个苹果。

The same two lines in ruby 1.9 produce (not wanted)

ruby 1.9中相同的两行生成(不需要)

In the first quarter we sold ["2"] ["Apple"] (s).

第一季度我们卖出了[2][苹果][s]。

After reading in the documentation Ruby 1.9.3 doc#Array#slice I thought I could produce code like

在阅读了Ruby 1.9.3 doc#Array#slice文档之后，我认为我可以生成类似的代码

reportStr = "In the first quarter we sold " + myArray[3] + " " + myArray[0] + "(s)."
puts reportStr

which returns a runtime error

哪个返回运行时错误

/home/test/example.rb:450:in `+': can't convert Array into String (TypeError)

/home/test/example.在' +':不能将数组转换成字符串(类型错误)

My current solution is to remove brackets and quotation marks with a temporary string, like

我现在的解决方案是用一个临时字符串来删除括号和引号。

tempStr0 = myArray[0].to_s
myLength = tempStr0.length
tempStr0 = tempStr0[2..myLength-3]
tempStr3 = myArray[3].to_s
myLength = tempStr3.length
tempStr3 = tempStr3[2..myLength-3]
reportStr = "In the first quarter we sold " + tempStr3 + " " + tempStr0 + "(s)."
puts reportStr

which in general works.

一般的工作。

However, what would be a more elegant "ruby" way how to do that?

然而，如何用一种更优雅的“ruby”方式来实现这一点呢?

4 个解决方案

#1

Use interpolation instead of concatenation:

使用插值代替连接:

reportStr = "In the first quarter we sold #{myArray[3]} #{myArray[0]}(s)."

It's more idiomatic, more efficient, requires less typing and automatically calls to_s for you.

它更习惯，更高效，需要更少的输入，并自动为你调用to_s。

#2

You can use the .join method.

您可以使用.join方法。

For example:

例如:

my_array = ["Apple", "Pear", "Banana"]

my_array.join(', ') # returns string separating array elements with arg to `join`

=> Apple, Pear, Banana

#3

And if you need to do this for more than one fruit the best way is to transform the array and the use the each statement.

如果你需要对不止一个结果执行此操作，最好的方法是转换数组并使用每个语句。

myArray = ["Apple", "Pear", "Banana", "2", "1", "12"]
num_of_products = 3

tranformed = myArray.each_slice(num_of_products).to_a.transpose
p tranformed #=> [["Apple", "2"], ["Pear", "1"], ["Banana", "12"]]

tranformed.each do |fruit, amount|
  puts "In the first quarter we sold #{amount} #{fruit}#{amount=='1' ? '':'s'}."
end 

#=>
#In the first quarter we sold 2 Apples.
#In the first quarter we sold 1 Pear.
#In the first quarter we sold 12 Bananas.

#4

You can think of this as arrayToString()

可以将其看作arrayToString()

array = array * " "

数组=数组* " "

E.g.,

例如,

myArray = ["One.","_1_?! Really?!","Yes!"]

myArray =(“。”、“_1_ ? !真的吗? !”,“是的!”)

=> "One.","_1_?! Really?!","Yes!"

= > "。”、“_1_ ? !真的吗? !”,“是的!”

myArray = myArray * " "

myArray = myArray "

=> "One. _1_?! Really?! Yes."

= > "。_1_ ? !真的吗? !是的。”

#1