HTML5 phone number validation with pattern

Question

I\'m using HTML5 form validation to validate phone numbers from India.

Phone numbers from India are 10 digits long, and start with 7, 8, or 9.

For example:

Answer 1

The regex validation for india should make sure that +91 is used, then make sure that 7, 8,9 is used after +91 and finally followed by 9 digits.

/^+91(7\d|8\d|9\d)\d{9}$/

Your original regex doesn't require a "+" at the front though.

Get the more information from below link
w3schools.com/jsref/jsref_obj_regexp.asp