正则表达式用于将字符串与红宝石中的数字匹配

Question

I have a string as below.

"Included in PTA fees" or "Included in PTA fees 33$" or "Included in PTA fees $60"

I need to match this string with searching for PTA fee/fees and whether any fee(number) is also appended with it.

Need to look for "PTA fees" along with fee value in any given string and return true.

So it should return true for

"Included in PTA fees 33$" and
"Included in PTA fees $60"

It should return false for "Included in PTA fees"

I tried with below regular expression. but it returns true for

"Included in PTA fees"

/#{PTA_FEE[0-9]}/i.match?(value)

Answer 1

This regex should work

^.*PTA fees?(?=.*(?:(?:\d+\s*\$)|(?:\$\s*\d+)))

Regex Breakdown

(?i) #Ignore Case
^ #Start of string
.*
PTA fees? #Match the string with fee(s)
(?=.* #Lookahead

  (?: #Non capturing group

     (?:\d+\s*\$) #Match digit followed by $

        | #Alternation

     (?:\$\s*\d+) #Match $ followed digit

  ) #End non capturing group
) #End lookahead

rubular demo

Answer 2

You simply need \\S+ as end part of your regex:

str =~ /Included in PTA fees? \S+/

• \\S+ One or more non-whitespace character(s)
• ? Optional match

or to be more precise:

str =~ /Included in PTA fees? (?:\d+\$|\$\d+)/

Live demo

Answer 3

I'd go with Included in PTA fees(?=.*?(\\d+(?:\\.\\d+)?)) ; this also groups the fee and takes into account floating-point values. But it doesn't take into account any free-form negation such as " aren't included in PTA fees" or " not included in PTA fees".

It disregards the dollar sign; since your description is incomplete and what you're matching against looks like something that is potentially grammatically incorrect, you may have \\$\\s*\\d+|\\d+\\s*\\$ for the dollar sign. Does the dollar value potentially have a thousand separator?

You can complicate the answer to this question quite a lot when the problem is under-specified.

Answer 4

You can use this one:

^Included in PTA fees\s*(\$\d+|\d+\$)

It checks if string starts with Included in PTA fees and then allows fee number with a dollar sign before ( \\$\\d+ ) or after it ( \\d+\\$ )

Demo