I replace my string as below;
string str = "Opps V 14";
str = str.Replace("V 14", "V14");
But numeric part of string is not static. Sometimes it can be "V 17", "V 13" etc..
How can I replace that with regular expressions globally?
This will replace the space between V and a digit with nothing:
string pattern = #"(?<=\bV) (?=\d)";
Regex rgx = new Regex(pattern);
string result = rgx.Replace(str, "");
(?<=\bV) is a lookbehind assertion and means "preceded by V", \b is a word boundary.
(?=\d) is a lookahead assertion and means "followed by a digit"
Lookaround assertions are not part of the match result but only checks. This is the reason why only the space is removed.
note: you must include using System.Text.RegularExpressions; at the begining of the file.
Assuming that except the number, rest of the string is static, then its as simple as removing the space after V:
str = str.Replace("V ","V");
class Program
{
static void Main(string[] args)
{
string str = "Opps V 14";
string[] temp = str.Split(' ');
str = String.Join(" ", temp.Take(2)) + temp.Last();
}
}
Related
Need to replace all forward-slash (/) with > except for the ones in the square brackets
input string:
string str = "//div[1]/li/a[#href='https://www.facebook.com/']";
Tried pattern (did not work):
string regex = #"\/(?=$|[^]]+\||\[[^]]+\]\/)";
var pattern = Regex.Replace(str, regex, ">");
Expected Result:
">>div[1]>li>a[#href='https://www.facebook.com/']"
Your thinking was good with lookbehind but instead positive use negative.
(?<!\[[^\]]*)(\/)
Demo
After updating your c# code
string pattern = #"(?<!\[[^\]]*)(\/)";
string input = "//div[1]/li/a[#href='https://www.facebook.com/']";
var result = Regex.Replace(input, pattern, ">");
You will get
>>div[1]>li>a[#href='https://www.facebook.com/']
If you're willing to also use String.Replace you can do the following:
string input = "//div[1]/li/a[#href='https://www.facebook.com/']";
string expected = ">>div[1]>li>a[#href='https://www.facebook.com/']";
var groups = Regex.Match(input, #"^(.*)(\[.*\])$")
.Groups
.Cast<Group>()
.Select(g => g.Value)
.Skip(1);
var left = groups.First().Replace('/', '>');
var right = groups.Last();
var actual = left + right;
Assert.Equal(expected, actual);
What this does is split the string into two groups, where for the first group the / is replaced by > as you describe. The second group is appended as is. Basically, you don't care what is between square brackets.
(The Assert is from an xUnit unit test.)
You could either match from an opening till a closing square bracket or capture the / in a capturing group.
In the replacement replace the / with a <
Pattern
\[[^]]+\]|(/)
\[[^]]+\] Match from opening [ till closing ]
| Or
(/) Capture / in group 1
Regex demo | C# demo
For example
string str = "//div[1]/li/a[#href='https://www.facebook.com/']";
string regex = #"\[[^]]+\]|(/)";
str = Regex.Replace(str, regex, m => m.Groups[1].Success ? ">" : m.Value);
Console.WriteLine(str);
Output
>>div[1]>li>a[#href='https://www.facebook.com/']
I have string in text that have uses | as a delimiter.
Example:
|2P|1|U|F8|
I want the result to be 2P|1|U|F8. How can I do that?
The regex is very easy, but why not just use Trim():
var str = "|2P|1|U|F8|";
str = str.Trim(new[] {'|'});
or just without new[] {...}:
str = str.Trim('|');
Output:
In case there are leading/trailing whitespaces, you can use chained Trims:
var str = "\r\n |2P|1|U|F8| \r\n";
str = str.Trim().Trim('|');
Output will be the same.
You can use String.Substring:
string str = "|2P|1|U|F8|";
string newStr = str.Substring(1, str.Length - 2);
Just remove the starting and the ending delimiter.
#"^\||\|$"
Use the below regex and then replace the match with an empty string.
Regex rgx = new Regex(#"^\||\|$");
string result = rgx.Replace(input, "");
Use mulitline modifier m when you're dealing with multiple lines.
Regex rgx = new Regex(#"(?m)^\||\|$");
Since | is a special char in regex, you need to escape this in-order to match a literal | symbol.
string input = "|2P|1|U|F8|";
foreach (string item in input.Split("|".ToCharArray(), StringSplitOptions.RemoveEmptyEntries))
{
Console.WriteLine(item);
}
Result is:
2P
1
U
F8
^\||\|$
You can try this.Replace by empty string.Use verbatim mode.See demo.
https://regex101.com/r/oF9hR9/14
For completionists-sake, you can also use Mid
Strings.Mid("|2P|1|U|F8|", 2, s.Length - 2)
This will cut out the part from the second character to the previous to last one and produce the correct output.
I'm assuming that at some point you will want to parse the string to extract its '|' separated components, so here goes another alternative that goes in that direction:
string.Join("|", theString.Split(new[] {'|'}, StringSplitOptions.RemoveEmptyEntries))
I want to check multiple words in a string and want to replace them. Suppose that my string is
str= 20148(R)/(work)24553(r)
if(str.contains(("R)" || str.Contains("(work)"))
{
//Here I have to replace (R) and (Work) with space "".
// so that my string should be like this 20148/24553
}
How can check multiple words not by using loops, and in one flow.
I am new to c#. Please help me out
You don't need the if, just do:
var newStr = str.Replace("(R)"," ").Replace("(work)"," ");
If you want a space as you say or:
var newStr = str.Replace("(R)",string.Empty).Replace("(work)",string.Empty);
If you want an empty string.
Put R and r inside a character class to match both letters.
string str = "20148(R)/(work)24553(r)";
string result = Regex.Replace(str, #"\((?:[Rr]|work)\)", "");
Console.WriteLine(result);
IDEONE
OR
string str = "20148(R)/(work)24553(r)";
string result = Regex.Replace(str, #"(?i)\((?:R|work)\)", "");
Console.WriteLine(result);
IDEONE
Pattern Explanation:
(?i) (i modifier) would turn on the case-insensitive mode. So it would match both upper and lowercase letters.
\( Matches a literal ( symbol.
(?:) Non-capturing group.
R|work Matches a letter R or string work.(case-insensitive match)
\) Matches a literal ) symbol.
You could use the Regex.Replace method.
string str = "20148(R)/(work)24553(r)";
string str2 = Regex.Replace(str, "[(](?:R|work)[)]", "", RegexOptions.IgnoreCase);
Console.Writeline(str2); //prints 20148/24553
This says take the string str and match the pattern [(R|work)] and replace any instances with "" ignoring the case of the input string when doing the comparison (so it matches (R) and (r)).
With regex you can replace this
[(]\b(?:R|work)\b[)]
With empty string ""
Edit:
string str1 = "20148(R)/(work)24553(r)";
string str2 = Regex.Replace(str1, "[(]\b(?:R|work)\b[)]", "", RegexOptions.IgnoreCase);
Console.Writeline(str2);
I'm trying to replace all alphanumeric characters in my string with the character "-" using regex. So if the input is "Dune" i should get "----". currently though I'm getting just the single "-";
string s = "^[a-zA-Z0-9]*$";
Regex rgx = new Regex(s);
string s = "dune";
string result = rgx.Replace(s, "-");
Console.WriteLine(result);
Console.Read();
right now i know its looking for the string "dune" rather then the letters "d" "u" "n" "e". but i can find another class that would work.
Your regex is too greedy, remove the * and start end string matches. It should be
string s = "[a-zA-Z0-9]";
This will then only match 1 character anywhere in the string rather than all. You could also look at the shorthand for any alphanumeric
String s= "\w";
Try
string s = "[a-zA-Z0-9]";
Regex rgx = new Regex(s);
string s = "dune";
string result = rgx.Replace(s, "-");
Console.WriteLine(result);
Console.Read();
Why do you have one String s for your regular expression and another String s for your string? I would change this to eliminate confusion/error here.
Also to replace each alphanumeric character, you need to remove the beginning of string/end of string anchors ^ $ and the * quantifier meaning (0 or more times, matching the most amount possible)
Regex rgx = new Regex("[a-zA-Z0-9]");
string s = "dune";
string result = rgx.Replace(s, "-");
Console.WriteLine(result); //=> "----"
Problem:
Cannot find a consistent way to replace a random string between quotes with a specific string I want. Any help would be greatly appreciated.
Example:
String str1 = "test=\"-1\"";
should become
String str2 = "test=\"31\"";
but also work for
String str3 = "test=\"foobar\"";
basically I want to turn this
String str4 = "test=\"antyhingCanGoHere\"";
into this
String str4 = "test=\"31\"";
Have tried:
Case insensitive Regex without using RegexOptions enumeration
How do you do case-insensitive string replacement using regular expressions?
Replace any character in between AnyText: and <usernameredacted#example.com> with an empty string using Regex?
Replace string in between occurrences
Replace a String between two Strings
Current code:
Regex RemoveName = new Regex("(?VARIABLE=\").*(?=\")", RegexOptions.IgnoreCase);
String convertSeccons = RemoveName.Replace(ruleFixed, "31");
Returns error:
System.ArgumentException was caught
Message=parsing "(?VARIABLE=").*(?=")" - Unrecognized grouping construct.
Source=System
StackTrace:
at System.Text.RegularExpressions.RegexParser.ScanGroupOpen()
at System.Text.RegularExpressions.RegexParser.ScanRegex()
at System.Text.RegularExpressions.RegexParser.Parse(String re, RegexOptions op)
at System.Text.RegularExpressions.Regex..ctor(String pattern, RegexOptions options, Boolean useCache)
at System.Text.RegularExpressions.Regex..ctor(String pattern, RegexOptions options)
at application.application.insertGroupID(String rule) in C:\Users\winserv8\Documents\Visual Studio 2010\Projects\application\application\MainFormLauncher.cs:line 298
at application.application.xmlqueryDB(String xmlSaveLocation, TextWriter tw, String ruleName) in C:\Users\winserv8\Documents\Visual Studio 2010\Projects\application\application\MainFormLauncher.cs:line 250
InnerException:
found answer
string s = Regex.Replace(ruleFixed, "VARIABLE=\"(.*)\"", "VARIABLE=\"31\"");
ruleFixed = s;
I found this code sample at Replace any character in between AnyText: and with an empty string using Regex? which is one of the links i previously posted and just had skipped over this syntax because i thought it wouldnt handle what i needed.
var str1 = "test=\"foobar\"";
var str2 = str1.Substring(0, str1.IndexOf("\"") + 1) + "31\"";
If needed add check for IndexOf != -1
I don't know if I understood you correct, but if you want to replace all chars inside string, why aren't you using simple regular expresission
String str = "test=\"-\"1\"";
Regex regExpr = new Regex("\".*\"", RegexOptions.IgnoreCase);
String result = regExpr.Replace(str , "\"31\"");
Console.WriteLine(result);
prints:
test="31"
Note: You can take advantage of plain old XAttribute
String ruleFixed = "test=\"-\"1\"";
var splited = ruleFixed.Split('=');
var attribute = new XAttribute(splited[0], splited[1]);
attribute.Value = "31";
Console.WriteLine(attribute);//prints test="31"
var parts = given.Split('=');
return string.Format("{0}=\"{1}\"", parts[0], replacement);
In the case that your string has other things in it besides just the key/value pair of key="value", then you need to make the value-match part not match quote marks, or it will match all the way from the first value to the last quote mark in the string.
If that is true, then try this:
Regex.Replace(ruleFixed, "(?<=VARIABLE\s*=\s*\")[^\"]*(?=\")", "31");
This uses negative look-behind to match the VARIABLE=" part (with optional white space around it so VARIABLE = " would work as well, and negative look-ahead to match the ending ", without including the look-ahead/behind in the final match, enabling you to just replace the value you want.
If not, then your solution will work, but is not optimal because you have to repeat the value and the quote marks in the replace text.
Assuming that the string within the quotes does not contain quotes itself, you can use this general pattern in order to find a position between a prefix and a suffix:
(?<=prefix)find(?=suffix)
In your case
(?<=\w+=").*?(?=")
Here we are using the prefix \w+=" where \w+ denotes word characters (the variable) and =" are the equal sign and the quote.
We want to find anything .*? until we encounter the next quote.
The suffix is simply the quote ".
string result = Regex.Replace(input, "(?<=\\w+=\").*?(?=\")", replacement);
Try this:
[^"\r\n]*(?:""[\r\n]*)*
var pattern = "\"(.*)?\"";
var regex = new Regex(pattern, RegexOptions.IgnoreCase);
var replacement = regex.Replace("test=\"hereissomething\"", "\"31\"");
string s = Regex.Replace(ruleFixed, "VARIABLE=\"(.*)\"", "VARIABLE=\"31\"");
ruleFixed = s;
I found this code sample at Replace any character in between AnyText: and <usernameredacted#example.com> with an empty string using Regex? which is one of the links i previously posted and just had skipped over this syntax because i thought it wouldnt handle what i needed.
String str1 = "test=\"-1\"";
string[] parts = str1.Split(new[] {'"'}, 3);
string str2 = parts.Length == 3 ? string.Join(#"\", parts.First(), "31", parts.Last()) : str1;
String str1 = "test=\"-1\"";
string res = Regex.Replace(str1, "(^+\").+(\"+)", "$1" + "31" + "$2");
Im pretty bad at RegEx but you could make a simple ExtensionMethod using string functions to do this.
public static class StringExtensions
{
public static string ReplaceBetweenQuotes(this string str, string replacement)
{
if (str.Count(c => c.Equals('"')) == 2)
{
int start = str.IndexOf('"') + 1;
str = str.Replace(str.Substring(start, str.LastIndexOf('"') - start), replacement);
}
return str;
}
}
Usage:
String str3 = "test=\"foobar\"";
str3 = str3.ReplaceBetweenQuotes("31");
returns: "test=\"31\""