使用Ruby中的正则表达式计算字符串内数字和字符的长度

Question

how to counting length of number and character inside string using regex in ruby? if i have some case like this, how to resolve it? example :

abc = "12345678a"

after counting using regex, i want get result like this :

number = 8
char = 1

how to do that?

Answer 1

Try following

abc = "12345678a"
abc.scan(/\d/).length
# => 8 
abc.scan(/\D/).length
# => 1 

Answer 2

No regex:

abc = "12345678a"
p abc.count("0-9") # => 8
p abc.count("a-zA-Z") # => 1

Answer 3

This is an optional, but I still think regex is better.

irb(main):051:0> number, char = abc.bytes.to_a.partition { |e| e >= 48 and e <= 57}
=> [[49, 50, 51, 52, 53, 54, 55, 56], [97]]
irb(main):053:0> number.count
=> 8
irb(main):054:0> char.count
=> 1

partition: Returns two arrays, the first containing the elements of enum for which the block evaluates to true, the second containing the rest.