Question

I need a regexp to check the String “incould \w,-,. and not start with .”
I hope the result is

abc ->false

ab_c ->false

a-b_c.->false

a@-b_C. ->true

.a-b_c. ->true

I tried /[^\w-\.]/ only “.a-b_c.” was fail, I get false (I hope be true)
and I tried /^\./ can be “.a-b_c.” true, but other was fail.

has any body can help me?

Answer 1

If you need to match string including only \w, - or . and not starting with ., then try this:

/^(?!\.)[\w.-]+$/

Details:

• ^ – search from start of string
• (?!\.) – don’t match if there is . symbol at this position
• [\w.-]+ – match to more than 1 symbols from \w.- set
• $ – match to end of string

Testing:

• abc -> matched
• ab_c -> matched
• a-b_c. -> matched
• a@-b_C. -> not matched
• .a-b_c. -> not matched