Phone number validation with plus sign optional

问题

How can i validate a phone number with plus sign optional only at the beginning and after that any number of digits with number only.

I tried this:-

/^\+(?:[\d]*)$/

How will be the modification

回答1:

/^\+?(?:[\d]*)$/

The questionmark tells that the plus sign can be there or not. However, your expression can be optimized quite a bit:

/^\+?\d+$/ 

I changed the * to a + as the expression would match just a plus sign. \d* suggests that it should match 0 or more digits.

Here's a demo on Regexr.

来源：https://stackoverflow.com/questions/29555521/phone-number-validation-with-plus-sign-optional