将字符串数字（以字格式）转换为整数ruby
如果你有一个字符串ten ，可以在Ruby中将它转换为整数10吗？ （也许在铁轨？）
我重视tryruby.org的开发人员，在他们的教程中，它特别说“to_i将事物转换为整数（数字。）”我想知道为什么他们没有说“to_i将STRINGS转换为整数（数字。）”
哪些变量类型可以从它们的类型转换为整数？
查看此gem以处理字对数转换。
从自述文件：
require 'numbers_in_words' require 'numbers_in_words/duck_punch' 112.in_words #=> one hundred and twelve "Seventy million, five-hundred and fifty six thousand point eight nine three".in_numbers #=> 70556000.893
我该怎么做
def n_to_s(int) set1 = ["","one","two","three","four","five","six","seven", "eight","nine","ten","eleven","twelve","thirteen", "fourteen","fifteen","sixteen","seventeen","eighteen", "nineteen"] set2 = ["","","twenty","thirty","forty","fifty","sixty", "seventy","eighty","ninety"] thousands = (int/1000) hundreds = ((int%1000) / 100) tens = ((int % 100) / 10) ones = int % 10 string = "" string += set1[thousands] + " thousand " if thousands != 0 if thousands > 0 string += set1[hundreds] + " hundred" if hundreds != 0 string +=" and " if tens != 0 || ones != 0 string = string + set1[tens*10+ones] if tens < 2 string += set2[tens] string = string + " " + set1[ones] if ones != 0 string << 'zero' if int == 0 p string end
为了测试的目的;
n_to_s(rand(9999))
由于String#to_i只选择数字字符，因此无法按照您想要的方式工作。 可能有一些与此相关的Rails方法，但肯定不会有方法名称to_i因为它的行为将与String#to_i的原始意图冲突。
它不仅仅是Strings to_i 。 NilClass ， Time ， Float ， Rational （也许还有其他一些类）也可以。
"3".to_i #=> 3 "".to_i #=> 0 nil.to_i #=> 0 Time.now.to_i #=> 1353932622 (3.0).to_i #=> 3 Rational(10/3).to_i #=> 3
这是一个简单的字符串查找到它们的数字等价：
str_to_int_hash = { 'zero' => 0, 'one' => 1, 'two' => 2, 'three' => 3, 'four' => 4, 'five' => 5, 'six' => 6, 'seven' => 7, 'eight' => 8, 'nine' => 9, 'ten' => 10 } str_to_int_hash['ten'] => 10
很明显还有很多其他缺失的条目，但它说明了这个想法。
如果你想从一个数字到字符串，这是一个起点：
int_to_str_hash = Hash[str_to_int_hash.map{ |k,v| [v,k] }] int_to_str_hash[10] => "ten"