如何从ruby中的字符串中提取子字符串？

Question

I have a repeated string="I will email you at xxx@gmail.com" and I want to pull out just the actual email address.

How can I pull just the email out?

Note: Ideally, I'd also like to deal with user-error where the format may be "I will email you at my email xxx@gmail.com" . In this case, the user input "my email xxx@gmail.com" and I just want the email address.

Answer 1

Relatively permissive regex that will work with your example:

"I will email you at xxx@gmail.com".match(/\b\S+@\S+\b/).to_s
#=> "xxx@gmail.com"

See also this RFC-compliant regex .

Answer 2

You can do this:

[6] pry(main)> string="I will email you at xxx@gmail.com"
=> "I will email you at xxx@gmail.com"
[7] pry(main)> string.scan(/[A-Za-z\d_\-\.+]+@[A-Za-z\d_\-\.]+\.[A-Za-z\d_\-]+/)
=> ["xxx@gmail.com"]
[8] pry(main)> str2 = "I will email you at my email xxx@gmail.com"
=> "I will email you at my email xxx@gmail.com"
[9] pry(main)> string.scan(/[A-Za-z\d_\-\.+]+@[A-Za-z\d_\-\.]+\.[A-Za-z\d_\-]+/)
=> ["xxx@gmail.com"]

There's some good reading on this subject at " How to Find or Validate an Email Address "