Javascript Regular Expressions

Basic Validations using reg exp: 

 Check Numbers : /\d+/g

 AlphaNumaric: /^[A-Z0-9]*$/

 AllZeros: /^[0]*$/

 12 Numbers : /\b\d{12}\b/

Any Sequence in any format :

Ex1 : /\b[X]{1}[A-Z]{1}\d{6}[A-Z0-9]{1}\b/

output is : X123456A || X1234569

Ex2 : /\b[U]{1}[F]{1}\d{5}[A-Z]{1}\b/ 

output is : UF12345A

var regExp="/\b\d{6}\b/";

var sampleStr="123456"

regExp.test(sampleStr) returns true.


To test the sample data use below online testers

https://regex101.com/
https://www.regextester.com/

How to test reg Exp :
reg Exp : \b\d{4}\b

if you enter 1234 it will show 1 Match found
other than this it will show No Match found