Regex with at least 3 alpha and allows numerics and specials chars

Question

The regexp what i'm searching for is :

• must contains 3 alpha chars at first
• allows numerics values
• allows dash, dot and underscore

Examples :

test1546 = OK

vqa._96 = OK

1test_ = KO

_test1546 = KO

Thank's a lot! ;)

Answer 1

Try this regular expression:

/^[a-zA-Z]{3}[\w.-]*$/

Explanation:

• The ^ matches the start of the string.
• The $ matches the end of the string.
• The [a-zA-Z]{3} means match three letters.
• The \w matches [A-Za-z0-9_].