I'm processing input from a Web form. Basically, all I care about is that the value provided includes 10 digits, no more, no less.
These would be valid inputs:
1234567890
123 456 789 0 Hello!
My number is: 123456-7890 thanks
These would be invalid inputs:
123456789033 (too long)
123 Hello! (too short)
My number is one five zero nine thanks (no digits)
I've tried many different things with Regextester but it never matches correctly. I'm using the 'preg' setting (which is what I figured my CMS Typo3 uses) and my closest attempt is:
([0-9][^0-9]*){10}
which is kinda lame but is the closest I got.
Cheers!
EDIT: I cannot use any programming language to implement this. Imagine that I have a admin console field in front of me, in which I must enter a regular expression that will be used to validate the value. That's all the latitude I have. Cheers.
I think you've got the right idea. Maybe you can simplify it as (\d\D*){10}
If the regex has to match the complete string, you would want \D*(\d\D*){10}
UPDATE: It looks like you need ^\D*(\d\D*){10}$ to make sure you match the complete string.
A regular expression is not always the best tool for this kind of job. In this case it's probably easier and simpler to write a function to count the number of digits in a string. (Since you didn't mention a programming language, I'll use Python in my example.)
def count_digits(s):
return len([x for x in s if x.isdigit()])
Then, you can use it like this:
s = "My number is: 123456-7890 thanks"
if count_digits(s) == 10:
print("looks okay")
else:
print("doesn't contain 10 digits")
Related
I checked around but didn't find a regular expression that was suitable. I'm trying to match on only numbers (8-32) and tried a few combinations that were unsuccessful including (Regex regex = new Regex("[8-9]|[10-29]\\d",RegexOptions.IgnoreCase | RegexOptions.Singleline);). This only got me up to 8-29 and then I got lost.
I know there is a better and easier way if I just create an if statement, but I'll never learn anything doing it that way. :-)
Any help would be greatly appreciated.
Using a regex for checking whether a number is in a range is a bad idea. Regex only cares about what characters are in the string, not what the value of each character represents. The regex engine doesn't know that 2 in 23 actually means 20. To it, it's the same as any other 2.
You might be able to write a highly complex regex to do that, but don't.
Assuming you are using C#, just convert the string to an integer like this
var integer = Convert.ToInt32(yourString);
then check if it is in range with an if statement:
if (integer >= 8 && integer <= 32) {
}
If your number is a part of a larger string, then you can use regex to extract the number out, convert it to an int, and check it with an if.
As a reference for regex testing with explanations, I would suggest you https://regexr.com/
And for your need : 8-32, you will want a pattern like
[8-9]|[1-2][0-9]|3[0-2]
So that you will get 8 or 9 or every number between 10 and 29 or 30 to 32
I'm currently using ([1-9]|1[0-2]) to represent inputs from 1 to 12. (Leading zeros not allowed.)
However it seems rather hacky, and on some days it looks outright dirty.
☞ Is there a proper in-built way to do it?
☞ What are some other ways to represent number ranges?
I tend to go with forms like [2-9]|1[0-2]? which avoids backtracking, though it makes little difference here. I've been conditioned by XML Schema to avoid such "ambiguities", even though regex can handle them fine.
Yes, the correct one:
[1-9]|1[0-2]
Otherwise you don't get the 10.
Here is the better answer, with exact match from 1 - 12.
(^0?[1-9]$)|(^1[0-2]$)
Previous answers doesn't really work well with HTML input regex validation, where some values like '1111' or '1212' will still treat it as a valid input.
You can use:
[1-9]|1[012]
How about:
^[1-9]|10|11|12$
Matches 0-9 or 10 or 11 or 12. thats it, nothing else is matched.
You can try this:
^[1-9]$|^[1][0-2]$
Use the following pattern (0?[1-9]|1[0-2]) use this which will return values from 1 to 12 (January to December) even if it initially starts with 0 (01, 02, 03, ..., 09, 10, 11, 12)
The correct patter to validate numbers from 1 to 12 is the following:
(^[1-9][0-2]$)|(^[1-9]$)
The above expression is useful when you have an input with type number and you need to validate month, for example. This is because the input type number ignores the 0 in front of any number, eg: 01 it returns 1.
You can see it in action here: https://regexr.com/5hk0s
if you need to validate string numbers, I mean, when you use an input with type text but you expect numbers, eg: expiration card month, or months the below expression can be useful for you:
((^0[1-9]$)|(^1[0-2]$))
You can see it in action here https://regexr.com/5hkae
I hope this helps a lot because it is very tricky.
Regards.
In python this matches any number between 1 - 12:
12|11|10|9|8|7|6|5|4|3|2|1
The descending order matters. In ascending order 10, 11 and 12 would match 1 instead as regex usually pick the first matching value.
I am currently trying to validate UK telephone numbers:
The format I'm looking for is: 01234 567891 or 01234567891 - So I need the number to have 5 numbers then a space then 6 numbers or simply a 11 numbers.
The number must start with a 0.
I've had a look at a couple of examples:
/^[0-9]{10,11} - to check that the chars are all numbers
/^0[0-9]{9,10}$/ - to check that the first number is a 0
I'm just unsure how to put all these together and check if there is a space or not.
Could someone help me with this regex?
Thanks
Try this regex:
/^0\d{4}\s?\d{6}$/
Many people try to do input validation and formatting in a single step.
It is better to separate these processes.
Match UK telephone number in any format
^(?:(?:\(?(?:0(?:0|11)\)?[\s-]?\(?|\+)44\)?[\s-]?(?:\(?0\)?[\s-]?)?)|(?:\(?0))(?:(?:\d{5}\)?[\s-]?\d{4,5})|(?:\d{4}\)?[\s-]?(?:\d{5}|\d{3}[\s-]?\d{3}))|(?:\d{3}\)?[\s-]?\d{3}[\s-]?\d{3,4})|(?:\d{2}\)?[\s-]?\d{4}[\s-]?\d{4}))(?:[\s-]?(?:x|ext\.?|\#)\d{3,4})?$
The above pattern allows the user to enter the number in any format they are comfortable with. Don't constrain the user into entering specific formats.
Extract NSN, prefix and extension
^(\(?(?:0(?:0|11)\)?[\s-]?\(?|\+)(44)\)?[\s-]?)?\(?0?(?:\)[\s-]?)?([1-9]\d{1,4}\)?[\d[\s-]]+)((?:x|ext\.?|\#)\d{3,4})?$
Next, extract the various elements.
$2 will be '44' if international format was used, otherwise assume national format with leading '0'.
$4 contains the extension number if present.
$3 contains the NSN part.
Validation and formatting
Use further RegEx patterns to check the NSN has the right number of digits for this number range. Finally, store the number in E.164 format or display it in E.123 format.
There's a very detailed list of validation and display formatting RegEx patterns for UK numbers at:
http://www.aa-asterisk.org.uk/index.php/Regular_Expressions_for_Validating_and_Formatting_UK_Telephone_Numbers
It's too long to reproduce here and it would be difficult to maintain multiple copies of this document.
If you are looking for all UK numbers, I'd look for a bit more than just that number, some are in the format 020 7123 4567 etc.
^\s*\(?(020[7,8]{1}\)?[ ]?[1-9]{1}[0-9{2}[ ]?[0-9]{4})|(0[1-8]{1}[0-9]{3}\)?[ ]?[1-9]{1}[0-9]{2}[ ]?[0-9]{3})\s*$
/\d*(*)*+*-*/
Simple Telephone Regex includes + () and - anywhere, as well as digits
I think ^0[\d]{4}\s?[\d]{5,6}} will work for you. I have used [\d] instead of [0-9].
I find that RegExr is a useful online tool to check and try your regular expressions. It also has a nice library of examples to help point you in the right direction
you should just count the number of digits and check that it's 10,
Some UK numbers have only 9 digits, not 10 (not including the leading 0).
These include 40 of the 01 area codes (using "4+5" format), the 016977 area code (using "5+4" format), all 0500 numbers and some 0800 numbers.
There's a list at: http://www.aa-asterisk.org.uk/index.php/01_numbers
This US numbers pattern accepts following phones as well:
800-432-4500, Opt: 9, Ext: 100316
800-432-4500, Opt: 9, Ext: X100316
800-432-4500, Option #3
(?:(?:\+?1\s*(?:[.-]\s*)?)?(?:\(\s*([2-9]1[02-9]|[2-9][02-8]1|[2-9][02-8][02-9])\s*\)|([2-9]1[02-9]|[2-9][02-8]1|[2-9][02-8][02-9]))\s*(?:[.-]\s*)?)?([2-9]1[02-9]|[2-9][02-9]1|[2-9][02-9]{2})\s*(?:[.-]\s*)?([0-9]{4}),?(?:\s*(?:#|x\.?|opt(\.|:|\.:)?|option)\s*#?(\d+))?,?(?:\s*(?:#|x\.?|ext(\.|:|\.:)?|extension)\s*(\d+))?
(used this answer in other topic as start point)
I have a list of numbers that I want to find at least 3 of...
here is an example
I have a large list of numbers in a sql database in the format of (for example)
01-02-03-04-05-06
06-08-19-24-25-36
etc etc
basically 6 random numbers between 0 and 99.
Now I want to find the strings where at least 3 of a set of given numbers occurs.
For example:
given: 01-02-03-10-11-12
return the strings that have at least 3 of those numbers in them.
eg
01-05-06-09-10-12 would match
03-08-10-12-18-22 would match
03-09-12-18-22-38 would not
I am thinking that there might be some algorithm or even regular expression that could match this... but my lack of computer science textbook experience is tripping me up I think.
No - this is not a homework question! This is for an actual application!
I am developing in ruby, but any language answer would be appreciated
You can use a string replacement to replace - with | to turn 01-02-03-10-11-12 into 01|02|03|10|11|12. Then wrap it like this:
((01|02|03|10|11|12).*){3}
This will find any of the digit pairs, then ignore any number of characters... 3 times. If it matches, then success.
I have a website form that requires a US phone number input for follow up purposes, and this is very necessary in this case. I want try to eliminate users entering junk data 330-000-0000. I have seen some options of third parties that validate phone numbers for you, however idk if that is the best option for this situation. However if you have every used one of these third parties and can make a recommendation that would also be greatly appreciated here.
However I am considering checking the number against a set of rules to just try to narrow down the junk phone numbers received.
not a 555 number
does not contain 7 identical digits
valid area code (this is readily available)
not a 123-1234 or 123-4567
I guess I could also count out 867-5309 (heh*)
Would this result in any situations that you can think of that would not allow a user to enter their phone number? Could you think of any other rules that a phone number should not contain? Any other thoughts?
It seems to me that you're putting more effort into this than it warrants. Consider:
If your purpose is to guard against mis-entered phone numbers, then you can probably catch well over 90% of them with just a very simple check.
If your purpose is to try to force users to provide a valid number whether they want to give that information out or not, then you've taken on a hopeless task - even if you were able to access 100% accurate, up-to-the-second telco databases to verify that the exact number entered is currently live, you still don't gain any assurance that the number they gave you is their own. Once again, a simple check will foil the majority of people entering bogus numbers, but those who are willing to try more than two or three times will find a way to defeat your attempts to gain their numbers.
Either way, a simple test is going to get you good results and going into more complex rule sets will take up increasingly more time while providing increasingly little benefit to you (while also potentially adding false positives, as already shown with the "seven of the same digit" and 867-5309 cases).
You can do phone number validation internally in your app using regular expressions. Depending on your language you can call a function that will return true if a supplied phone number matches the expression.
In PHP:
function phone_number_is_valid($phone) {
return (eregi('^(?:\([2-9]\d{2}\)\ ?|[2-9]\d{2}(?:\-?|\ ?))[2-9]\d{2}[- ]?\d{4}$', $phone));
}
You can look up different regular expressions online. I found the one above one at http://regexlib.com/DisplayPatterns.aspx?categoryId=7&cattabindex=2
Edit: Some language specific sites for regular expressions:
PHP at php.net: http://php.net/regex
C# at MSDN
Java: http://java.sun.com/developer/technicalArticles/releases/1.4regex/
867-5309 is a valid phone number that is assigned to people in different area codes.
If you can verify the area code then unless you really, really need to know their phone number you're probably doing as much as is reasonable.
In Django there is a nice little contrib package called localflavor wich has a lot of country specific validation code, for example postal codes or phone numbers. You can look in the source too see how django handles these for the country you would like to use; For example: US Form validation. This can be a great recourse for information about countries you know little of as well.
Your customers can still do what I do, which is give out the local moviefone number.
Also, 123-1234 or 123-4567 are only invalid numbers because the prefix begins with a 1, but 234-5678 or 234-1234 would actually be valid (though it looks fake).
Maybe take a look at the answers to this question.
If you're sticking with just US- and Canada-format numbers, I think the following regex might work:
[2-9][0-9][0-9]-[2-9][0-9][0-9]-[0-9][0-9][0-9][0-9] & ![2-9][0-9][0-9]-555-[0-9][0-9][0-9][0-9]
You also need to take into account ten-digit dialing, which is used in some areas now: this is different from long-distance dialing (ie, 303-555-1234, as opposed to 1-303-555-1234). In some places, a valid phone number is ten digits long; in others, it is seven.
This is a quick function that I use (below). I do have access to a zipcode database that contains areacode and prefix data which is updated monthly. I have often thought about doing a data dip to confirm that the prefix exists for the area code.
public static bool isPhone(string phoneNum)
{
Regex rxPhone1, rxPhone2;
rxPhone1 = new Regex(#"^\d{10,}$");
rxPhone2 = new Regex(#"(\d)\1\1\1\1\1\1\1\1\1");
if(phoneNum.Trim() == string.Empty)
return false;
if(phoneNum.Length != 10)
return false;
//Check to make sure the phone number has at least 10 digits
if (!rxPhone1.IsMatch(phoneNum))
return false;
//Check for repeating characters (ex. 9999999999)
if (rxPhone2.IsMatch(phoneNum))
return false;
//Make sure first digit is not 1 or zero
if(phoneNum.Substring(0,1) == "1" || phoneNum.Substring(0,1) == "0")
return false;
return true;
}
I don't nkow if this is the right place, it's a formatting function rather than a validation function, I thought let's share it with the community, maybe one day it will be helpful..
Private Sub OnNumberChanged()
Dim sep = "-"
Dim num As String = Number.ToCharArray.Where(Function(c) Char.IsDigit(c)) _
.ToArray
Dim ext As String = Nothing
If num.Length > 10 Then ext = num.Substring(10)
ext = If(IsNullOrEmpty(ext), "", " x" & ext)
_Number = Left(num, 3) & sep & Mid(num, 4, 3) & sep & Mid(num, 7, 4) & ext
End Sub
My validation function is like so:
Public Shared Function ValidatePhoneNumber(ByVal number As String)
Return number IsNot Nothing AndAlso number.ToCharArray. _
Where(Function(c) Char.IsNumber(c)).Count >= 10
End Function
I call this last function # the OnNumberChanging(number As String) method of the entity.
For US and International Phone validation I found this code the most suitable:
((\+[1-9]{1,4}[ \-]*)|(\([0-9]{2,3}\)[ \-]*)|([0-9]{2,4})[ \-]*)*?[0-9]{3,4}?[ \-]*[0-9]{3,4}?$
You can find an (albeit somewhat dated) discussion here.
Those parameters look pretty good to me, I might also avoid numbers starting with 911 just to be safe.