regex101: PCRE (Legacy) Match Workspace

#the literal # (35₁₀ / 43₈ / 23₁₆)

Group 1(\w*[0-9a-zA-Z]+\w*[0-9a-zA-Z])

\w*any word character, repeated any number of times

Character Class[0-9a-zA-Z]+

+matches at least one character from the set below:

0-9one character from 0 (48₁₀) to 9 (57₁₀)

a-zone character from a (97₁₀) to z (122₁₀) (case sensitive)

A-Zone character from A (65₁₀) to Z (90₁₀) (case sensitive)

\w*any word character, repeated any number of times

Character Class[0-9a-zA-Z]

0-9one character from 0 (48₁₀) to 9 (57₁₀)

a-zone character from a (97₁₀) to z (122₁₀) (case sensitive)

A-Zone character from A (65₁₀) to Z (90₁₀) (case sensitive)

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

Search reference

Regular Expression

#(\w*[0-9a-zA-Z]+\w*[0-9a-zA-Z])

New


//only accept az AZ and _ (underscore)

#teste_teste      //underscore accepted
#teste-teste 	    //Hyphen not accepted
#leof_gfg.sdfsd   //dot not accepted
#f34234@45#6fgh6  // @ not accepted
#leo#leo2#asd     //followed hastag without space 
#6663             // only number accepted
_#asd_            // hashtag can't start or finish with underscore
-#sdfsdf-         // hashtag can't start or finish with hyphen
.#sdfsdf.         // hashtag can't start or finish with dot


#leo_leo__leo__leo____leo //TO FIX: decline followed underline

Regular Expressions 101

Regular Expression

Substitution