I have not been able to find a proper regex to match any string not starting and ending with some condition.
This matches
AS.E
23.5
3.45
This doesn't match
.263
321.
.ASD
The regex can be alpha-numeric character with optional '.' character and it has to be with in range of 2-4(minimum 2 chars & maximum 4 chars).
I was able to create one ->
^[^\.][A-Z|0-9|\.]{2,4}$
but with this I couldn't achieve mask '.' character at the end of regex.
Thanks.
Maybe not the most optimized but a working one. Created step by step:
The first character should be alphanumeric
^[a-zA-Z0-9]
0, 1 or 2 character alphanumeric or . but not matching end of string
[a-zA-Z0-9\.]{0,2}
an alphanumeric character matching end of string
[a-zA-Z0-9]$
Concatenate all of this to obtain your regex
^[a-zA-Z0-9][a-zA-Z0-9\.]{0,2}[a-zA-Z0-9]$
Edit: This regex allows multiple dots (up to 2)
If I guessed correctly, you want to match all words that are
Between 2 and 4 characters long ...
... and start and end with a character from [A-Z0-9] ...
... and have characters from [A-Z0-9.] in the middle ...
... and are not preceded or followed by a ..
Try this regex to match all these substrings in a text:
(?<=^|[^.])[A-Z0-9][A-Z0-9.]{0,2}[A-Z0-9](?=$|[^.])
However, note that this will match the AA in .AAAA.. If you don't want this match, then please give more details on your requirements.
When you are only interested in the number of matches, but not the matched strings, then you could use
(^|[^.])[A-Z0-9][A-Z0-9.]{0,2}[A-Z0-9]($|[^.])
If you have one string, and want to know whether that string completely matches or not, then use
^[A-Z0-9][A-Z0-9.]{0,2}[A-Z0-9]$
If there may be at most one . inside the match, replace the part [A-Z0-9.]{0,2} with ([A-Z0-9]?[A-Z0-9.]?|[A-Z0-9.]?[A-Z0-9]?).
You can use this pattern to match what you say,
^[^\.][a-zA-Z0-9\.]{2,4}[^\.]$
Check the result here..
https://regex101.com/r/8BNdDg/3
Related
I used the following regex to catch 10 numbers and letters:
/[a-zA-Z0-9]{10}/g
It works fine if the 10 characters are only numbers and letters.
e.g. input: 12345xcdw034342
it catches 12345xcdw0
But in this case with special characters or space, it doesn't catch it.
123}456712234324Zz3 or 123}45 71223AB3
It should catch 10 numbers and letters regardness of characters.
Any help would be gratefully appreciated.
You can do it but not without any extra processing
As you have not spetified what language you're using Ill use Javascript for being quite universal but the same logic must apply in any language.
Here are the options I can think of
if I have testString = "12#34{56A789BDE"
Match the all until the first ten alphanumeric caracters, and then remove the spetial characters in the resulting string
testString.match(/(\w.*?){10}/)[0].replaceAll(/\W/g, '')
// results '123456A789'
// explanation: we take the first \w and use .*? to indicate that we dont care if the alphanumeric has a non-alphanumeric right next to it, then we clean the result by removing \W which means non-alphanumeric
Match only the first ten alphanumeric caracters and then join them to make a result string
testString.match(/\w/g).splice(0,10).join('')
// results '123456A789'
// explanation: we match 10 groups of aphanumeric characters represented by \w (note the lowercase) and we join the first 10 (using splice to get them) as each group "()" is in the case of javascript returned as an element of an array of matches
Remove the spetial characters from your string and then take the first ten
testString.replaceAll(/\W/g,'').match(/\w{10}/)[0]
// results '123456A789'
// explanation: we replace \W which means non alpha numeric characters, with '' to delete them then we match the first ten
You can use
/[a-zA-Z0-9](?:[^a-zA-Z0-9]*[a-zA-Z0-9]){9}/g
See the regex demo. Details:
[a-zA-Z0-9] - an alphanumeric
(?:[^a-zA-Z0-9]*[a-zA-Z0-9]){9} - nine occurrences of any zero or more chars other than an alphanumeric char and then an alphanumeric char.
This is my input:
0,0,0,1
1,023,1230,1,0
,1,0,01-09-2018,1,
I want to replace 0s and 1s whose length is 1. Rest of them will be as it is.
I already tried with javascript code i.e. split all the strings with "," as delimiter. Then, checking for strings with length 1 and replacing them as per logic. But that's a tedious method which consumes a lot of time.
I want a Regex that can do the replacements in entire input.
I have already tried with this regex: ((0|1)(?<=,))|((0|1)(?=,)). But the output is wrong
Output will be such:
N,N,N,Y
Y,023,1230,Y,N
,Y,N,01-09-2018,Y,
You can use the following regexps with comma word boundaries:
(?<![^,])1(?![^,])
(?<![^,])0(?![^,])
Replace with the appropriate substring.
They match 1 or 0 only when enclosed with commas or start/end of string positions.
(?<![^,]) - a negative lookbehind that matches a position not immediately preceded with a char other than ,
(?![^,]) - a negative lookahead that matches a position not immediately followed with a char other than ,.
I want to match 2~4 length string that containing at least one alphabet and one * by using Regex.
For example, test string is below:
124 adbaad aa1 efd f*ad *** af 848
(The special syntax of the input will not contain longer similar words, e.g. abc*def)
I want to match f*ad in the string.
[a-z*]{2,4}
I tried above regex but a string without * also matched.
I've searched the Internet for 2 days but I couldn't find solution.
How can I achieve the goal?
At the beginning of the pattern, lookahead for 0-3 alphabetical characters followed by a *, and also lookahead for 0-3 *s followed by an alphabetical character. This ensures that the match starts at a point followed by at least one alphabetical and at least one * within the next 4 characters. Then, match [a-z*]{2,4}:
(?=[a-z]{0,3}\*)(?=\*{0,3}[a-z])[a-z*]{2,4}
https://regex101.com/r/90A8rY/1
It's not clear from the question, but if you only want to match standalone words, lookbehind and lookahead for a space (or the edge of the string) at the start and end of the pattern:
(?<= |^)(?=[a-z]{0,3}\*)(?=\*{0,3}[a-z])[a-z*]{2,4}(?= |$)
^^^^^^^^ ^^^^^^^
https://regex101.com/r/90A8rY/3
I have the following regular expression:
/^[a-f0-9]{8}$/ --- This expression extracts an 8 character string as a md5 hash, for example: if I have the following string "hello world .305eef9f x1xxx 304ccf9f test1232" it will return "304ccf9f"
I also have the following regular expression:
/.[^.]*$/ --- This expression extracts a string after the last period (included), for example, if I have "hello world.this.is.atest.case9.23919sd3xxxs" it will return ".23919sd3xxxs"
Thing is, I've readen a bit about regex but I can't join both expressions in order to find the md5 string after the last period (included), for example:
topLeftLogo.93f02a9d.controller.99f06a7s ----> must return ".99f06a7s"
Thanks in advance for your time and help!
/^[a-f0-9]{8}$/ --- This expression extracts an 8 character string as a md5 hash
Yes but it doesn't return "304ccf9f" from "hello world .305eef9f x1xxx 304ccf9f test1232" because ^ in regex means start of string. How is it possible for it to match in middle of a string?
/.[^.]*$/ --- This expression extracts a string after the last period
No. It will do if you escape first dot only \.
To combine these two you have to replace ^ with \.:
\.[a-f0-9]{8}$
To match your characters 8 times after the last dot in this range [a-f0-9] you might use (if supported) a positive lookahead (?!.*\.) to match your values and assert that what follows does not contain a dot:
\.[a-f0-9]{8}(?!.*\.)
Regex demo
If you want to match characters from a-z instead of a-f like 99f06a7s you could use [a-z0-9]
About the first example
This regex ^[a-f0-9]{8}$ will match one of the ranges in the character class 8 times from the start until the end of the string due to the anchors ^ and $. It would not find a match in hello world .305eef9f x1xxx 304ccf9f test1232 on the same line.
About the second example
.[^.]*$ will match any character zero or more times followed by matching not a dot. That would for example also match a single a and is not bound to first matching a dot because you have to escape the dot to match it literally.
I'm adding this just in case people needs to solve a similar casuistic:
Case 1: for example, we want to get the hexadecimal ([a-f0-9]) 8 char string from our filename string
between the last period and the file extension, in order, for example, to remove that "hashed" part:
Example:
file.name2222.controller.2567d667.js ------> returns .2567d667
We will need to use the following regex:
\.[a-f0-9]{8}(?=\.\w+$)
Case 2: for example, we want the same as above but ignoring the first period:
Example:
file.name2222.controller.2567d667.js ------> returns 2567d667
We will need to use the following regex
[a-f0-9]{8}(?=\.\w+$)
Using this for an example string
+$43073$7
and need the 5 number sequence from it I'm using the Regex expression
#"\$+(?<lot>\d{5})"
which is matching up any +$ in the string. I tried
#"^\$+(?<lot>\d{5})"
as the +$ are always at the beginning of the string. What will work?
If you use anchor ^, you need to include the + symbol at the first and don't forget to escape it because + is a special meta character in regex which repeats the previous token one or more times.
#"^\+\$(?<lot>\d{5})"
And without the anchor, it would be like
#"\$(?<lot>\d{5})"
And get the 5 digit number you want from group index 1.
DEMO
I would match what you want:
\d+
or if you only want digits after "special" characters at the start of input:
^\W+(\d+)
grabbing group 1