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Regex first digits occurrence

My task is extract the first digits in the following string:
GLB=VSCA|34|speed|1|
My pattern is the following:
(?x:VSCA(\|){1}(\d.))
Basically I need to extract "34", the first digits occurrence after the "VSCA". With my pattern I obtain a group but would be possibile to get only the number? this is my c# snippet:
string regex = #"(?x:VSCA(\|){1}(\d.))";
Regex rx = new Regex(regex);
string s = "GLB=VSCA|34|speed|1|";
if (rx.Match(s).Success)
{
var test = rx.Match(s).Groups[1].ToString();
}

You could match 34 (the first digits after VSCA) using a positive lookbehind (?<=VSCA\D*) to assert that what is on the left side is VSCA followed by zero or times not a digit \D* and then match one or more digits \d+:
(?<=VSCA\D*)\d+
If you need the pipe to be after VSCA the you could include that in the lookbehind:
(?<=VSCA\|)\d+
Demo

This regex pattern: (?<=VSCA\|)\d+?(?=\|) will match only the number. (If your number can be negative / have decimal places you may want to use (?<=VSCA\|).+?(?=\|) instead)

You don't need Regex for this, you can simply split on the '|' character:
string s = "GLB=VSCA|34|speed|1|";
string[] parts = s.Split('|');
if(parts.Length >= 2)
{
Console.WriteLine(parts[1]); //prints 34
}
The benefit here is that you can access all parts of the original string based on the index:
[0] - "GLB=VSCA"
[1] - "34"
[2] - "speed"
[3] - "1"
Fiddle here

While the other answers work really well, if you really must use a regular expression, or are interested in knowing how to get to that straight away you can use a named group for the number. Consider the following code:
string regex = #"(?x:VSCA(\|){1}(?<number>\d.?))";
Regex rx = new Regex(regex);
string s = "GLB:VSCA|34|speed|1|";
var match = rx.Match(s);
if(match.Success) Console.WriteLine(match.Groups["number"]);

How about (?<=VSCA\|)[0-9]+?
Try it out here

How to extract all strings between brackets using c#? [duplicate]

This question already has answers here:
How do I extract text that lies between parentheses (round brackets)?
(19 answers)
Closed 4 years ago.
If I have a string such as:
"You id is (1) and your number is (0000000000)"
What is the best way to extract these these strings into a list of strings. The numbers between the brackets can increase in digits thus searching for the strings between the brackets is a better technique.
I can use the code below to extract the first string between brackets.
var myString = "You id is (1) and your number is (0000000000)";
var firstNumberBetweenBrackets = myString.Split('(', ')')[1]; // would return 1

Here is a LINQ solution:
var result = myString.Split().Where(x => x.StartsWith("(") && x.EndsWith(")")).ToList();
Values stored in result:
result[0] = (1)
result[1] = (0000000000)
And if you want only the numbers without the brackets use:
var result = myString.Split().Where(x => x.StartsWith("(") && x.EndsWith(")"))
.Select(x=>x.Replace("(", string.Empty).Replace(")", string.Empty))
.ToList();
Values stored in result:
result[0] = 1
result[1] = 0000000000

You can use Regex for this (https://regex101.com/r/T4Sdik/1):
Regex regex = new Regex(#"\(([^()]+)\)*");
foreach (Match match in regex.Matches("You id is (1) and your number is (0000000000)")
{
Console.WriteLine(match.Value);
}
This will print:
1
0000000000

If you only want to get strings of digits inside parentheses, you may use
var results = Regex.Matches(s, #"\((\d+)\)")
.Cast<Match>()
.Select(m => m.Groups[1].Value)
.ToList();
The results are in Group 1, so you need to access them with m.Groups[1].Value.
Regex details
\( - matches a literal (
(\d+) - Capturing group 1: one or more (due to the + quantifier) digits (you may use [0-9] instead of \d to only match ASCII digits, or use the RegexOptions.ECMAScript)
\) - a literal )
See the online C# demo and a regex demo here:

How to remove number character from string in c# [duplicate]

This question already has answers here:
How to remove the exact occurence of characters from a string?
(7 answers)
Closed 6 years ago.
i have a string like string st ="12,34,56,345,12,45" and i want remove number 34 from this string i did like string newst = st.replace(",34",""); but it is removing 34 from 345 , how to prevent this
EDIT
34 can be anywhere,here i am generating dynamically

It's very simple:
var st ="12,34,56,345,12,45";
var newst = st.replace(",34,", ",");
If it can be anywhere, you may use the regular expression:
var input = "34,234,35,36,34,37,345,34";
var pattern = #",?\b34\b,?";
var regex = new Regex(pattern);
var result = regex.Replace(input, ",").Trim(',');
Shorter notation could look like this:
var result = Regex.Replace(input, #",?\b34\b,?", ",").Trim(',');
Explanation of the regular expression: ,?\b34\b,? matches the word 34, but only if preceded and followed by word-delimiter characters (because of the word boundary metacharacter \b), and it can be (but doesn't have to be) preceded and followed by the comma thanks to ,? which means none or more comma(s).
At the end we need to remove possible commas from the beginning and end of the string, that's why there's Trim(',') on the result.
But I would say #crashmstr's solution is better than trying to tune the regular expression for this particular use case.

This will work:
var oldString = "34,12,34,56,345,12,45,34";
var newString = String.Join(",", oldString.Split(',').Where(x => x != "34"));
We split on ',', use LINQ to exclude "34", then join the string back together by ','.

Try this
string newst = st.replace(",34,",",");
Granted this only works if the number you want to replace is between two commas. If you want something more advanced, use Regex.Replace()
Here's an example:
string temp = Regex.Replace("12,34,56,345,12,45", #"^34,", "");
string newst = Regex.Replace(temp, #"34$,", "");
You could also use String.TrimStart and .TrimEnd to clean up the borders.
Also, I like crashmstr's example.

split and work in list:
string[] arr = st.Split(',');
List<string> list = arr.ToList();
list.Remove("34");
or regex:
var replaced = Regex.Replace(st, #"\b34\b[,]","");

splitting the string and choosing the middle part containing two set of parenthesis [duplicate]

This question already has answers here:
How do I extract text that lies between parentheses (round brackets)?
(19 answers)
Closed 7 years ago.
As I know for selecting a part of a string we use split. For example, if node1.Text is test (delete) if we choose delete
string b1 = node1.Text.Split('(')[0];
then that means we have chosen test, But if I want to choose delete from node1.Text how can I do?
Update:
Another question is that when there are two sets of parenthesis in the string, how one could aim at delete?. For example is string is test(2) (delete) - if we choose delete

You can also use regex, and then just remove the parentheses:
resultString = Regex.Match(yourString, #"\((.*?)\)").Value.
Replace("(", "").Replace(")", "");
Or better:
Regex.Match(yourString, #"\((.*?)\)").Groups[1].Value;
If you want to extract multiple strings in parentheses:
List<string> matches = new List<string>();
var result = Regex.Matches(yourString, #"\((.*?)\)");
foreach(Match x in result)
matches.Add(x.Groups[1].Value.ToString());

If your string is always xxx(yyy)zzz format, you can add ) character so split it and get the second item like;
var s = "test (delete) if we choose delete";
string b1 = s.Split(new[] { '(', ')' })[1];

string tmp = node1.Text.Split('(')[1];
string final = tmp.Split(')')[0];
Is also possible.
With the index [x] you target the part of the string before and after the character you have split the original string at. If the character occurs multiple times, your resulting string hat more parts.

Remove characters between different parameters [duplicate]

This question already has an answer here:
Learning Regular Expressions [closed]
(1 answer)
Closed 7 years ago.
I have a string of different emails
ex: "email1#uy.com, email2#iu.it, email3#uu.edu" etc, etc
I would like to formulate a Regex that creates the following output
ex: "email1,email2,email3" etc, etc
How can I remove characters between an "#" and "," but leaving a "," and a Space in C#
Thank you so much for the help!!

If you want to replace all characters between # and comma by blank, the easiest option is to use Regex.Replace:
var emails = "a#m.com, b#m.com, d#m.com";
var result = Regex.Replace(emails, "#[^,]+", string.Empty);
// result is "a, b, d"
Please note that it leaves spaces after comma in the result, as you wanted in your question, though your example result has spaces removed.
The regular expression looks for all substrings starting '#' characters, followed by any character which is not comma. Those substrings are replaced with empty string.

Replacing all occurrences of #[^,]+ with an empty string will do the job.
The expression matches sequences that start in #, inclusive, up to a comma or to the end, exclusive. Therefore, commas in the original string of e-mails would be kept.
Demo.

Maybe you don't need to use a regex, in that case you can do the following:
string input = "email1#uy.com, email2#iu.it, email3#uu.edu";
input = input.Replace(" ", "");
string[] ocurrences = input.Split(',');
for (int i = 0; i < ocurrences.Length; i++)
{
string s = ocurrences[i];
ocurrences[i] = s.Substring(0, s.IndexOf('#'));
}
string final = string.Join(", ", occurences);