正则表达式匹配第二个单词或另一个单词的第一个出现

Question

I have a situation where I need to parser the below content

Some Text
Some Text
SUB-TOTAL          :    $0.90 
Some Text          :    $0.79-
SUB-TOTAL          :    $0.11 
TAX                :    $0.05 
TOTAL      $0.16 

I need to parse till last 'SUB-TOTAL' if Tax does not exist, else it has to parse till TAX I am not sure where I did wrong in the regex * . ?(?=(TAX|(SUB-TOTAL. ?SUB-TOTAL))) * Since have less experience on regex. Can some one please help me out.

Thanks in advance.

Answer 1

To get up-to and including SUB-TOTAL or TAX with its value, you can use: .*(?:(?:SUB-TOTAL|TAX)[^\\n]*) ... Is that the right cut-off?

EDIT OK - made my head hurt... but to get last SUB-TOTAL if it exists, otherwise TAX:

^(?:(?:(?!.*SUB-TOTAL.*).*TAX[^\n]*)|(?:.*SUB-TOTAL[^\n]*))

Hope this works in your regex engine!

EDIT2 This version does not return the SUB-TOTAL/TAX line

^(?:(?:(?!.*SUB-TOTAL.*).*(?=TAX))|(?:.*(?=SUB-TOTAL)))