I have the following string:
"121 fd412 4151 3213, 421, 423 41241 fdsfsd"
And I need to get 3213 and 421 - because they both have space in front of them, and a coma behind.
The result will be set inside the string array...How can I do that?
"\\d+" catches every integer.
"\s\\d+(,)" throws some memory errors.
EDIT.
space to the left (<-) of the number, coma to the right (->)
EDIT 2.
string mainString = "Tests run: 5816, 8346, 28364 iansufbiausbfbabsbo3 4";
MatchCollection c = Regex.Matches(a, #"\d+(?=\,)");
var myList = new List<String>();
foreach(Match match in c)
{
myList.Add(match.Value);
}
Console.Write(myList[1]);
Console.ReadKey();
Your regex syntax is incorrect for wanting to match both digits, if you want them as separate results, you could do:
#"\s(\d+),\s(\d+)\s"
Live Demo
Edit
#"\s(\d+),"
Live Demo
\s\\d+(,):
\s is not properly escaped, should be \\s, same as for \\d
\\d matches single digit, you need \\d+ - one or more consecutive digits
(,) captures comma, do you really need this? seems like you need to capture a number, so \\s(\\d+),
you said "because they both have space behind them, and a coma in front", so probably ,\\s(\\d+)
How about this expression :
" \d+," // expression without the quotes
it should find what you need.
How to work with regular expression can you check on the MSDN
Hope it helps
Another solution
\s(\d+), // or maybe you'll need a double slash \\
Output:
3213
421
Demo
I think you mean you're looking for something like ,<space><digit> not ,<digit><space>
If so, try this:
, (\d+) //you might need to add another backslash as the others have noted
Well, based on your new edit
\s(\d+),
Test it here
It's all you need, only the numbers
\d+(?=\,)
Related
I want to chunk a credit card number (in my case I always have 16 digits) into 4 chunks of 4 digits.
I've succeeded doing it via positive look ahead :
var s="4581458245834584";
var t=Regex.Split(s,"(?=(?:....)*$)");
Console.WriteLine(t);
But I don't understand why the result is with two padded empty cells:
I already know that I can use "Remove Empty Entries" flag , But I'm not after that.
However - If I change the regex to (?=(?:....)+$) , then I get this result :
Question
Why does the regex emit empty cells ? and how can I fix my regex so it produce 4 chunks at first place ( without having to 'trim' those empty entries )
But I don't understand why the result is with two padded empty cells:
Let's try breaking down your regex.
Regex: (?=(?:....)*$)
Explanation: Lookahead (?=) for anything 4 times(?:....) for zero or more times. Just looking ahead and matching nothing will match zero width.
Since you are using * quantifier which says zero or more it matches first zero width at beginning or string and also at end of string.
Visualize it from this snapshot of Regex101 Demo
[
So How can I select only those 3 splitters in the middle ?
I don't know C# very well but this 3 step method might work for you.
Search with (\d{4}) and replace with -\1. Result will be -4581-4582-4583-4584. Demo
Now replace first - by searching with ^-. Result will be 4581-4582-4583-4584. Demo
At last search for - and split on it. Demo. Used \n to substitute for demo purpose.
Alternative Solution Inspired from Royi's answer.
Regex: (?=(?!^)(?:\d{4})+$)
Explanation:
(?= // Look ahead for
(?!^) // Not the start of string
(?:\d{4})+$ // Multiple group of 4 digits till end of string
)
Since nothing is matched and only lookaround assertions are used, it will pinpoint Zero width after a group of 4 digits.
Regex101 Demo
It seems like I've found an answer.
Looking at those splitters - I needed to get rid of the edges :
So I thought - how can I tell the regex engine "not at the start of the line " ?
Which is exactly what (?!^) does
So here is the new regex :
var s="4581458245834584";
var t=Regex.Split(s,"(?!^)(?=(?:....)+$)");
Console.WriteLine(t);
Result :
Umm, I don't know WHY you need Regex for this. You just overcomplicate things. Better way is to just split it manually:
var values = new List<int>();
for(int i =0;i < 4;i++)
{
var value = int.Parse(s.Substring(i*4, 4));
values.Add(value);
}
Regex solution:
var s = "4581458245834584";
var separated = Regex.Match(s, "(.{4}){4}").Groups[1].Captures.Cast<Capture>().Select(x => x.Value).ToArray();
It has been mentioned already that the * quantifier also matches at the end of string where there are zero group-matches ahead. To avoid matching at start and end you can use \B non word boundary which only matches between two word characters not giving matches for start and end.
\B(?=(?:.{4})+$)
See demo at regex101
Because the lookahead won't be triggered at start or end of the string you could even use *
I have the following string:
21>Please be specific. What do you mean by that?21>Hello are you there623>Simon?
I want to split it into:
21>Please be specific. What do you mean by that?
21>Hello are you there
623>Simon?
Basically the splitter is the numeric value (21 and 623 in this case) followed by the >.
My implementation is that I find the > char, then walk back until I find a non-numeric value.
So basically using sub-string and the like. But it's ugly and I am certain there is a better Regex implementation, but I don't know enough about it.
So can Regex be used here?
You can achieve that with look ahead and look behind, so that your match is the zero length area between what you want to split.
string s = "21>Please be specific. What do you mean by that?21>Hello are you there623>Simon?";
Regex reg = new Regex(#"(?<=\D)(?=\d+>)");
var r = reg.Split(s);
foreach(var i in r)
Console.WriteLine(i);
Will output
21>Please be specific. What do you mean by that?
21>Hello are you there
623>Simon?
Try with following regex. It matches the zero width between something and number>
Regex: (?<=\D)(?=\d+>) replaced with \n for demo.
Explanation:
(?<=\D) looks behind to see if it's not a number.
(?=\d+>) looks ahead to see if it's a number>.
And matched the zer0-width between them.
Regex101 Demo
Try: [0-9]+>
Explanation:
[0-9]+ At least 1 digit
> followed by >
It might make sense to replace the matches with \n$0, which will move them to individual lines.
I have this string: FOO_KEK_-150915
My current regex that is not working: FOO_([A-Z_])-150915
What is wrong with my regex, I'm trying to find files that starts with "FOO" and end with that number?
[A-Z_] matches exactly one character. So it would only match e.g. FOO_K-150915 or even FOO__-150915.
In order to match multiple characters, you need to specify the quantity, for example using +:
FOO_([A-Z_]+)-150915
FOO_([A-Z_]+)-150915
^^
You need to add quantifer * or + or {1,4} or else it will match just 1 and your regex will fail.
See demo.
https://regex101.com/r/vV1wW6/33
What I am trying to do is fairly simple, although I am running into difficulty. I have a string that is a url, it will have the format http://www.somedomain.com?id=someid what I want to retrive is the someid part. I figure I can use a regular expression but I'm not very good with them, this is what I tried:
Match match = Regex.Match(theString, #"*.?id=(/d.)");
I get a regex exception saying there was an error parsing the regex. The way I am reading this is "any number of characters" then the literal "?id=" followed "by any number of digits". I put the digits in a group so I could pull them out. I'm not sure what is wrong with this. If anyone could tell me what I'm doing wrong I would appreciated it, thanks!
No need for Regex. Just use built-in utilities.
string query = new Uri("http://www.somedomain.com?id=someid").Query;
var dict = HttpUtility.ParseQueryString(query);
var value = dict["id"]
You've got a couple of errors in your regex. Try this:
Match match = Regex.Match(theString, #".*\?id=(\d+)");
Specifically, I:
changed *. to .* (dot matches all non-newline chars and * means zero or more of the preceding)
added a an escape sequence before the ? because the question mark is a special charcter in regular expressions. It means zero or one of the preceding.
changed /d. to \d* (you had the slash going the wrong way and you used dot, which was explained above, instead of * which was also explained above)
Try
var match = RegEx.Match(theString, #".*\?id=(\d+)");
The error is probably due to preceding *. The * character in regex matches zero or more occurrences of previous character; so it cannot be the first character.
Probably a typo, but shortcut for digit is \d, not /d
. matches any character, you need to match one or more digits - so use a +
? is a special character, so it needs to be escaped.
So it becomes:
Match match = Regex.Match(theString, #".*\?id=(\d+)");
That being said, regex is not the best tool for this; use a proper query string parser or things will eventually become difficult to manage.
i need a certain string to be in this format:
[0000] anyword
so between the [] brackets i need 4 numbers, followed by a whitespace. after that only characters ranging from a to z and - characters are allowed.
so this should be allowed:
[0000] foo-bar
[0000] foo
[0000] foo-bar-foo
etc..
so far i have this:
\[[0-9]{4}\]\s
this matches the [0000] , so it maches the brackets with 4 numbers in it and the whitespace.
i can't seem to find something that allows charachters after that. i've tried putting a single "." at the end of the expression as this should match any character but this doesnt seem to be working.
\[[0-9]{4}\]\s^[A-Z]+[a-zA-Z]*$
the above isn't working either..
i need this expression as a Validationexpression for an asp.net custom validator.
any help will be appreciated
(\[[0-9]{4}\])\s+([A-z\-]+) should hopefully work. It'll capture the numbers and letters into two capture groups as well.
This works for your input: http://regexr.com/?30sb7. Unlike Cornstalk's answer it does not capture anything, and - can indeed be placed later in a range if it's escaped.
Try this one
#"\[[0-9]{4}\] [a-zA-Z]+(-[a-zA-Z]+)*"