Javascript RegEx to check a certain number of Numeric characters in string regardless of other characters

Question

I have a field which the user will be entering a 9 digit numeric string.

e.g. 975367865

However some users will be entering the 9 digit numeric string with seperators such as "-" and "/".

e.g. 9753/67/865 OR 9753-67-865

I want to make sure that the user has entered a minimum of 9 numbers even if the user has added the "-" & "/" somewhere in the string.

Hope that makes sense.

Many thanks for any help.

Alex K. · Accepted Answer · 2014-08-22 11:06:45Z

1

You could just remove anything that is not a number to give a nice normalized form:

var number = input.replace(/[^\d]/g, "");

var ok = number.length == 9;

answered Aug 22, 2014 at 11:06

Alex K.

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1 Comment

Use \D, [^\d] not.

Nordehinu · Accepted Answer · 2014-08-22 11:07:15Z

0

Match with a quantifier:

/^\d(?:\D*\d){8}$/

^$ are Anchors that asserts position at the start of end of the String. This asserts the entire match, but since you're only matching, you can leave them out!
\d matches a digit.
\D* skips ahead of any non-digits. Then a digit will be matched with \d.
This group is then quantified: (?: ){8} To assert that the later alternation is matched eight times. Parted with the first match, this asserts that 9 digits are present in the match!

answered Aug 22, 2014 at 11:07

Nordehinu

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vks · Accepted Answer · 2014-08-22 11:11:53Z

0

 (?=[\-\/]*[0-9][\-\/]*[0-9][\-\/]*[0-9][\-\/]*[0-9][\-\/]*[0-9][\-\/]*[0-9][\-\/]*[0-9][\-\/]*[0-9][\-\/]*[0-9]+[\-\/]*)(.*)

Though a rather long looking regex but works perfectly well for your case. Have a look at the demo.

answered Aug 22, 2014 at 11:11

vks

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