Question

I have the following string, which matches the following RegEx string. I would like it to not match.

Test String: yahoo.c!om

RegEx Pattern: [\w\-_]+(\.[\w\-_]+)+([\w\-\.,@?^=%&:/~\+#]*[\w\-\@?^=%&/~\+#])?

Using an online tester, I can validate that “yahoo.c!om” matches. I can’t figure out how modify the RegEx pattern to make it NOT match. Does anyone have any ideas? This RegEx stuff makes me want to jump off a building.

Answer 1

The . in regex matches any character (other than line breaks). So the . in:

[\w-_]+(.[\w-_]+)+([\w-.,@?^=%&:/~+#]*[\w-\@?^=%&/~+#])?
        ^
        ^
        ^

matches the ! from yahoo.c!om. Escape the . to match the literal . instead:

[\w-_]+(\.[\w-_]+)+([\w-.,@?^=%&:/~+#]*[\w-\@?^=%&/~+#])?
        ^^
        ^^
        ^^

That way, yahoo.c!om won’t match entirely.

You may want to “anchor” your regex with the “start”- and “end-of-input” meta characters (^ and $ respectively):

^[\w-_]+(\.[\w-_]+)+([\w-.,@?^=%&:/~+#]*[\w-\@?^=%&/~+#])?$