Javascript Regular Expression?

Question

Am working on password validation , I got stuck at looking for one RegEx ,

I need a RegEx which does not allow the password to start with numbers or which allows the password to start with alphabet .

I tried few RegEx like [^0-9] , [ /[a-z][A-Z/g] ] .

Kindly help me in this .

"which does not allow the password to start with numbers" --- please don't do that. Let your users make their own decision about what to start their passwords with. By adding some weird constraints you just make passwords less memorable for users. — zerkms
– zerkms, Commented Sep 7, 2012 at 5:10
Just because a client /asks/ for something doesn't mean you can't tell them they are an idiot (in nice words). — Jeremy J Starcher
– Jeremy J Starcher, Commented Sep 7, 2012 at 5:14

Joey · Accepted Answer · 2012-09-07 05:11:51Z

1

Fairly simple, actually:

^[^0-9]

will make sure the first character is not a digit. But as zerkms notes in a comment already, you're reducing password entropy that way, thus making the system less safe, actually.

answered Sep 7, 2012 at 5:11

Joey

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3 Comments

Jey Ravi Over a year ago

Error: SyntaxError: unterminated regular expression literal , i got this script error when i use the above RegEx .

Jey Ravi Over a year ago

can you help me in fixing this .

Naren Over a year ago

Make sure you're adding the slashes to indicate this is a regex. i.e., yourstring.match(/^[^0-9]/)

Vishal Suthar · Accepted Answer · 2012-09-07 05:35:38Z

0

This is the one you need:

^([^0-9]).*

Regex Demo

EDIT:

Javascript:

var regexmatch = /^([^0-9]).*/

if (regexmatch.test(YOUR_EXPRESSION)){ 
    // code stuff
}

edited Sep 7, 2012 at 5:35

answered Sep 7, 2012 at 5:26

Vishal Suthar

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2 Comments

Jey Ravi Over a year ago

Error: SyntaxError: unterminated regular expression literal

Vishal Suthar Over a year ago

I just editted the answer..I me know if it works for you..@JeyRavi

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