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
2
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
22
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
1
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
0
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
2
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
22
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
1
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
0
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。”