Regex to look for good phone numbers - regex

How do I write a regexp that looks for a good phone number in a string?
Match criteria:
last 4 characters are the same
last 3 characters are the same
last and 3rd last are 0
Example on matches:
1-310-123-4444
1-310-123-3444
1-310-123-4040

last 3 or 4 characters are the same
(\d)\1{2,3}$
last and 3rd last are 0
0\d0$
Final Expression
/(?:(\d)\1{2,3}$)|(?:0\d0$)/
Demo Page
http://regexr.com/39on2

I am not sure how a valid phone number should be formed in general, but if you're just looking to validate the last four digits, this will do what you are looking for: (\d-(?:\d{3}-){2}(?:(?:(\d)\2{3})|(?:\d(\d)\3{2})|(?:\d0\d0))). You can test it with various inputs here.

http://regexr.com/39omv
I come up with this one which works fine on all your 3 criteria so far, it seems.
pattern I use: \d-\d\d\d-\d\d\d-((\d)\2{3}|\d(\d)\3{2}|\d0\d0)

Related

Optimization of Regular Expression to match numbers bigger or equal to 50

I want to check if a number is 50 or more using a regular expression. This in itself is no problem but the number field has another regex checking the format of the entered number.
The number will be in the continental format: 123.456,78 (a dot between groups of three digits and always a comma with 2 digits at the end)
Examples:
100.000,00
50.000,00
50,00
34,34
etc.
I want to capture numbers which are 50 or more. So from the four examples above the first three should be matched.
I've come up with this rather complicated one and am wondering if there is an easier way to do this.
^(\d{1,3}[.]|[5-9][0-9]|\d{3}|[.]\d{1,3})*[,]\d{2}$
EDIT
I want to match continental numbers here. The numbers have this format due to internal regulations and specify a price.
Example: 1000 EUR would be written as 1.000,00 EUR
50000 as 50.000,00 and so on.
It's a matter of taste, obviously, but using a negative lookahead gives a simple solution.
^(?!([1-4]?\d),)[1-9](\d{1,2})?(\.\d{3})*,\d{2}\b
In words: starting from a boundary ignore all numbers that start with 1 digit OR 2 digits (the first being a 1,2,3 or 4), followed by a comma.
Check on regex101.com
Try:
EDIT ^(.{3,}|[5-9]\d),\d{2}$
It checks if:
there 3 chars or more before the ,
there are 2 numbers before the , and the first is between 5 and 9
and then a , and 2 numbers
Donno if it answer your question as it'll return true for:
aa50,00
1sdf,54
But this assumes that your original string is a number in the format you expect (as it was not a requirement in your question).
EDIT 3
The regex below tests if the number is valid referring to the continental format and if it's equal or greater than 50. See tests here.
Regex: ^((([1-9]\d{0,2}\.)(\d{3}\.){0,}\d{3})|([1-9]\d{2})|([5-9]\d)),\d{2}$
Explanation (d is a number):
([1-9]\d{0,2}\.): either d., dd. or ddd. one time with the first d between 1 and 9.
(\d{3}\.){0,}: ddd. zero or x time
\d{3}: ddd 3 digit
These 3 parts combined match any numbers equals or greater than 1000 like: 1.000, 22.002 or 100.000.000.
([1-9]\d{2}): any number between 100 and 999.
([5-9]\d)): a number between 5 and 9 followed by a number. Matches anything between 50 and 99.
So it's either the one of the parts above or this one.
Then ,\d{2}$ matches the comma and the two last digits.
I have named all inner groups, for better understanding what part of number is matched by each group. After you understand how it works, change all ?P<..> to ?:.
This one is for any dec number in the continental format.
^(?P<common_int>(?P<int>(?P<int_start>[1-9]\d{1,2}|[1-9]\d|[1-9])(?P<int_end>\.\d{3})*|0)(?!,)|(?P<dec_int_having_frac>(?P<dec_int>(?P<dec_int_start>[1-9]\d{1,2}|[1-9]\d|[1-9])(?P<dec_int_end>\.\d{3})*,)|0,|,)(?=\d))(?P<frac_from_comma>(?<=,)(?P<frac>(?P<frac_start>\d{3}\.)*(?P<frac_end>\d{1,3})))?$
test
This one is for the same with the limit number>=50
^(?P<common_int>(?P<int>(?P<int_start>[1-9]\d{1,2}|[1-9]\d|[1-9])(?P<int_end>\.\d{3})+|(?P<int_short>[1-9]\d{2}|[5-9]\d))(?!,)|(?P<dec_int_having_frac>(?P<dec_int>(?P<dec_int_start>[1-9]\d{1,2}|[1-9]\d|[1-9])(?P<dec_int_end>\.\d{3})+,)|(?P<dec_short_int>[1-9]\d{2}|[5-9]\d),)(?=\d))(?P<frac_from_comma>(?<=,)(?P<frac>(?P<frac_start>\d{3}\.)*(?P<frac_end>\d{1,3})))?$
tests
If you always have the integer part under 999.999 and fractal part always 2 digits, it will be a bit more simple:
^(?P<dec_int_having_frac>(?P<dec_int>(?P<dec_int_start>[1-9]\d{1,2}|[1-9]\d|[1-9])(?P<dec_int_end>\.\d{3})?,)|(?P<dec_short_int>[1-9]\d{2}|[5-9]\d),)(?=\d)(?P<frac_from_comma>(?<=,)(?P<frac>(?P<frac_end>\d{1,2})))?$
test
If you can guarantee that the number is correctly formed -- that is, that the regex isn't expected to detect that 5,0.1 is invalid, then there are a limited number of passing cases:
ends with \d{3}
ends with [5-9]\d
contains \d{3},
contains [5-9]\d,
It's not actually necessary to do anything with \.
The easiest regex is to code for each of these individually:
(\d{3}$|[5-9]\d$|\d{3},|[5-9]\d)
You could make it more compact and efficient by merging some of the cases:
(\d{3}[$,]|[5-9]\d[$,])
If you need to also validate the format, you will need extra complexity. I would advise against attempting to do both in a single regex.
However unless you have a very good reason for having to do this with a regex, I recommend against it. Parse the string into an integer, and compare it with 50.

Regex for validation of a street number

I'm using an online tool to create contests. In order to send prizes, there's a form in there asking for user information (first name, last name, address,... etc).
There's an option to use regular expressions to validate the data entered in this form.
I'm struggling with the regular expression to put for the street number (I'm located in Belgium).
A street number can be the following:
1234
1234a
1234a12
begins with a number (max 4 digits)
can have letters as well (max 2 char)
Can have numbers after the letter(s) (max3)
I came up with the following expression:
^([0-9]{1,4})([A-Za-z]{1,2})?([0-9]{1,3})?$
But the problem is that as letters and second part of numbers are optional, it allows to enter numbers with up to 8 digits, which is not optimal.
1234 (first group)(no letters in the second group) 5678 (third group)
If one of you can tip me on how to achieve the expected result, it would be greatly appreciated !
You might use this regex:
^\d{1,4}([a-zA-Z]{1,2}\d{1,3}|[a-zA-Z]{1,2}|)$
where:
\d{1,4} - 1-4 digits
([a-zA-Z]{1,2}\d{1,3}|[a-zA-Z]{1,2}|) - optional group, which can be
[a-zA-Z]{1,2}\d{1,3} - 1-2 letters + 1-3 digits
or
[a-zA-Z]{1,2} - 1-2 letters
or
empty
\d{0,4}[a-zA-Z]{0,2}\d{0,3}
\d{0,4} The first groupe matches a number with 4 digits max
[a-zA-Z]{0,2} The second groupe matches a char with 2 digit in max
\d{0,3} The first groupe matches a number with 3 digits max
You have to keep the last two groups together, not allowing the last one to be present, if the second isn't, e.g.
^\d{1,4}(?:[a-zA-z]{1,2}\d{0,3})?$
or a little less optimized (but showing the approach a bit better)
^\d{1,4}(?:[a-zA-z]{1,2}(?:\d{1,3})?)?$
As you are using this for a validation I assumed that you don't need the capturing groups and replaced them with non-capturing ones.
You might want to change the first number check to [1-9]\d{0,3} to disallow leading zeros.
Thank you so much for your answers ! I tried Sebastian's solution :
^\d{1,4}(?:[a-zA-z]{1,2}\d{0,3})?$
And it works like a charm ! I still don't really understand what the ":" stand for, but I'll try to figure it out next time i have to fiddle with Regex !
Have a nice day,
Stan
The first digit cannot be 0.
There shouldn't be other symbols before and after the number.
So:
^[1-9]\d{0,3}(?:[a-zA-Z]{1,2}\d{0,3})?$
The ?: combination means that the () construction does not create a matching substring.
Here is the regex with tests for it.

Regex to categorize phone numbers that 2 of the last 4 digits the same.

Regex to categorize phone numbers. Numbers with 2 of the same digit in the last 4 not adjacent to each other are easier to remember and therefore more valuable. So given 10 digit number how can I match if 2 of the last 4 digits are the same non consecutively? Ex. 2155553747, 2158558284, 7034651215. Thanks in advance for the help.
If you want to use a regular expression for that, and you are okay with the condition, that at least 2 digits of the last 4 digits are the same, you could use the following regular expression:
^\d{6}(?:(\d)\d\d\1|(\d)\d\2\d|(\d)\3\d\d|\d(\d)\d\4|\d(\d)\5\d|\d\d(\d)\6)$
Here is a live example: https://regex101.com/r/t6n1uP/1
Masochistic approach:
/^\d{6}(\d?0[^0]{1,2}0|\d?1[^1]{1,2}1|\d?2[^2]{1,2}2|\d?3[^3]{1,2}3|\d?4[^4]{1,2}4|\d?5[^5]{1,2}5|\d?6[^6]{1,2}6|\d?7[^7]{1,2}7|\d?8[^8]{1,2}8|\d?9[^9]{1,2}9)/m
A test
Far from ideal, but something to start from

Regular expression for 7 digit numbers separeted by commas

I need a regular expression to validate a concatenated string that consists of 7 digit numbers separated by commas.
Furthermore, I must ensure that:
The string is not empty.
The chain doesn't begins or finish with commas.
The numbers do not start with 0.
Example: 1234567,2345678,3456789
My solution so far: ^\d+(,\d+)*?$
The problems I still need to resolve:
Validate that the numbers are exactly 7 digits.
Validate that the numbers do not start with 0.
Thank you.
Something like ^[1-9]\d{6}(,[1-9]\d{6})+$ should work. The [1-9] ensures the number doesn't begin with 0, and \d{6} ensures that there are 6 digits to follow.
Based on Gavin answer, here is what worked for me : ^[1-9]\d{6}(,[1-9]\d{6})*$
The minor difference is the use of the * instead of + at the end of the regular expression. There are some cases where I must validate only one 7 digits number...
Thank you for the help everyone!

Regex - how to make sure a string contain a word and numbers

I need a little help with Regex.
I want the regex to validate the following sentences:
fdsufgdsugfugh PCL 6
dfdagf PCL 11
fdsfds PCL6
fsfs PCL13
kl;klkPCL6
fdsgfdsPCL13
some chars, than PCL and than 6 or a greater number.
How this can be done?
I'd go with something like this:
^(.*)(PCL *)([6-9][0-9]*|[1-5][0-9]+)$
Meaning:
(.*) = some chars
(PCL *) = then PCL with optional whitespaces afterwards
([6-9][0-9]*|[1-5][0-9]+) then 6 or a greater number
This one should suit your needs:
^.*PCL\s*(?:[6-9]|\d{2,})$
Visualization by Debuggex
In bash:
EXPR=^[a-zA-Z]\+ *PCL *\([6-9]\|[0-9]\{2,\}\)
Translated:
Line begins with at least 1 occurence of a character (ignore caps)
Any amount of spaces, PCL, any amount of spaces
Either a number between 6 or 9, or a number with at least 2 digits
This expression used with something like grep "$EXPR" file.txt will output in stdout the lines that are valid.
This worked well for me. Reads logically too according to the way you described the matching
/[^PCL]+PCL\s?*[6-9]\d*/