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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?

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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