从数组

Question

我有一个简单的数组

arr = ["Japan", "Egypt", "Spain", "Brazil",....]

我想提取每个元素并使其成为哈希

japan = Hash.new("Japan")

egypt = Hash.new("Egypt")

brazil = Hash.new("Brazil")

最终将所有哈希存储在一个灌篮哈希

中

country = {"Japan" => 0, "Egypt" => 0,"Brazil" => 0,.....}

Answer 1

试试这个。

country = {}
arr.each do |name|
  country[name] = 0
end

Answer 2

我不确定您想要做什么，但您可以尝试以下方法：

arr = ["Japan", "Egypt", "Spain", "Brazil"]
arr.each { |a| Object.const_set(a, Hash.new(a)) } #initialize hashes

Country = arr.map {|a| [a, 0]}.to_h
#=> {"Japan"=>0, "Egypt"=>0, "Spain"=>0, "Brazil"=>0}

或

Country = Hash[arr.map {|a| [a, 0]}]
#=> {"Japan"=>0, "Egypt"=>0, "Spain"=>0, "Brazil"=>0}

注意：Ruby变量应为小写，如japan和egypt，常量应为大写，如JAPAN和EGYPT 。

Answer 3

要获得您指定为请求输出的结果：

countries = ["Japan", "Egypt", "Spain", "Brazil"]
countries_hash = countries.zip([0] * countries.size).to_h
#⇒ {"Japan"=>0, "Egypt"=>0, "Spain"=>0, "Brazil"=>0}

Answer 4

我认为reduce会有所帮助：

arr = ["Japan", "Egypt", "Spain", "Brazil",....]
arr.reduce({}) do |hash, element|
  hash[element] = 0
  hash
end

Answer 5

最明显的：

countries.map { |country| [country, 0] }.to_h