regex - How to return the substring of a string between two strings in Ruby?

Question

How would I return the string between two string markers of a string in Ruby?

For example I have:

• input_string
• str1_markerstring
• str2_markerstring

Want to do something like:

input_string.string_between_markers(str1_markerstring, str2_markerString)

Example text:

s
# => "Charges for the period 2012-01-28 00:00:00 to 2012-02-27 23:59:59:<br>
Any Network Cap remaining: $366.550<br>International Cap remaining: $0.000"
str1_markerstring
# => "Charges for the period"
str2_markerstring
# => "Any Network Cap"
s[/#{str1_markerstring}(.*?)#{str2_markerstring}/, 1]
# => nil  # IE DIDN'T WORK IN THIS CASE

Using Ruby 1.9.3.

Answer 1

input_string = "blahblahblahSTARTfoofoofooENDwowowowowo"
str1_markerstring = "START"
str2_markerstring = "END"

input_string[/#{str1_markerstring}(.*?)#{str2_markerstring}/m, 1]
#=> "foofoofoo"

or to put it in a method:

class String
  def string_between_markers marker1, marker2
    self[/#{Regexp.escape(marker1)}(.*?)#{Regexp.escape(marker2)}/m, 1]
  end
end

"blahblahblahSTARTfoofoofooENDwowowowowo".string_between_markers("START", "END")
#=> "foofoofoo"