I am working on the following regex problem that I have almost solved.

The goal is to find the words that start either with special characters or a space and end with one of these words including the period .qvd .txt .xlsx

For example "list.xlsx random %ford.txt #catch.qvd cars roads"

From above string I need to extract the following list.xlsx , ford.txt and catch.qvd

 [#%\S]\w \. txt

My solution only checks the words that end with .txt. How can I change my regex expression to include .qvd , and .xlsx too

CodePudding user response：

In this pattern [#%\S]\w \. txt the \S also matches $ and % and is the same as \S\w \. txt.

That would require a string that starts with a non whitespace char and will include "special chars" in the match, and the string must be at least 2 characters long.

If there can be either a "special char" or a space or the start of the string to the left, you can start the match directly with word characters, followed by matching any of the alternatives using a non capture group (?:txt|qvd|xlsx) and a word boundary \b at the end to prevent a partial word match.

\w \.(?:txt|qvd|xlsx)\b

Regex demo

CodePudding user response：

Use the | (alternation operator/metacharacter) to express an "or" relation between two or more subexpressions:

(?<!\S)[#%]\S \.(?:txt|qvd|xslx)