Validating date range in asp net
On the contrary, the 555 prefix is reserved for fake-out phone numbers. In my opinion, the most elegant solution is to validate a minimum length, nothing more.
Those numbers are guaranteed not to connect to an actual phone number so they're often used in television and movies to ensure that a viewer doesn't try to call the number and end up harassing some poor [email protected] While that was true decades ago, it is no longer true. After reading through these answers, it looks like there wasn't a straightforward regular expression that can parse through a bunch of text and pull out phone numbers in any format (including international with and without the plus sign).
If he does not want to give it to you then forcing him to enter a valid number will either send him to a competitor's site or make him enter a random string that fits your regex. For instance, 911 is a valid number in the US, but 911x isn't for any value of x.
I might even be tempted to look up the number of a premium rate sex line and enter that instead. That's so that the phone company can calculate when you are done dialing. But your regex doesn't check the area code portion, so that doesn't seem to be a concern.
The 555 prefix is still special, but only a small range of numbers are guaranteed to terminate without connection 555-0100 to 555-0199. This is good and all, but it doesn't validate what was entered was actually a phone number. Here's what I used for a client project recently, where we had to convert all phone numbers in any format to tel: links.
For example, what if the user doesn't enter the requisite 10 digits? So far, it's been working with everything they've thrown at it, but if errors come up, I'll update this answer.
If the phone number is wrong, the auth might [email protected] But regex validation won't help you. How are extensions (e.g., 111-222-3333 x 44444) going to be handled? If the user puts in a number you can't recognize as a valid number, either save it as inputted or strip out undailable characters.
The one and the only way to actually validate if the phone number is correct is to actually send a message to it (in case of mobile) AND make sure the user confirms using some kind of verification code. The Number:: Phone:: Normalize Perl module could be a source of inspiration.
If the user wants to give you his phone number, then trust him to get it right. The question should probably be specified in a bit more detail to explain the purpose of validating the numbers.
I would also consider any of the following as valid entries on a web site: I agree with the sentiment here, but sometimes it's nice to perform validation when the phone number is actually going to be used for something important in the interest of the user. Like validating email addresses, even if you have a valid result you can't know if it's assigned to someone until you try it.
Best example here is credit card authorization for a purchase. Here's a regex for a 7 or 10 digit number, with extensions allowed, delimiters are spaces, dashes, or periods: ^(? If you are trying to validate user input, why not normalize the result and be done with it?
This is what you do when the number correctness is important. I work for a market research company and we have to filter these types of input alllll the time. Just strip the non-alphanumeric chars, and see if there's an extension.
Everything else is just for user's convenience to protect against some (but not all) typos and does not validate anything. For further analysis you can subscribe to one of many providers that will give you access to a database of valid numbers as well as tell you if they're landlines or mobiles, disconnected, etc. @Plex Q 555-123-1234, 07777777777, 90210, 01/01/1901 - users are inventive in ramming garbage through validation.It turns out that there's something of a spec for this, at least for North America, called the NANP. Better to not tic off the ones who genuinely do have some odd data by using overly restrictive validation and telling them they're wrong.