I am trying to replace a certain group to "" by using regex.
I was searching and doing my best, but it's over my head.
What I want to do is,
string text = "(12je)apple(/)(jj92)banana(/)cat";
string resultIwant = {apple, banana, cat};
In the first square bracket, there must be 4 character including numbers.
and '(/)' will come to close.
Here's my code. (I was using matches function)
string text= #"(12dj)apple(/)(88j1)banana(/)cat";
string pattern = #"\(.{4}\)(?<value>.+?)\(/\)";
Regex rex = new Regex(pattern);
MatchCollection mc = rex.Matches(text);
if(mc.Count > 0)
{
foreach(Match str in mc)
{
print(str.Groups["value"].Value.ToString());
}
}
However, the result was
apple
banana
So I think I should use replace or something else instead of Matches.
The below regex would capture the word characters which are just after to ),
(?<=\))(\w+)
DEMO
Your c# code would be,
{
string str = "(12je)apple(/)(jj92)banana(/)cat";
Regex rgx = new Regex(#"(?<=\))(\w+)");
foreach (Match m in rgx.Matches(str))
Console.WriteLine(m.Groups[1].Value);
}
IDEONE
Explanation:
(?<=\)) Positive lookbehind is used here. It sets the matching marker just after to the ) symbol.
() capturing groups.
\w+ Then it captures all the following word characters. It won't capture the following ( symbol because it isn't a word character.
Related
I have a scenario where i want to extract some substring based on following condition.
search for any pattern myvalue=123& , extract myvalue=123
If the "myvalue" present at end of the line without "&", extract myvalue=123
for ex:
The string is abcdmyvalue=123&xyz => the it should return myvalue=123
The string is abcdmyvalue=123 => the it should return myvalue=123
for first scenario it is working for me with following regex - myvalue=(.?(?=[&,""]))
I am looking for how to modify this regex to include my second scenario as well. I am using https://regex101.com/ to test this.
Thanks in Advace!
Some notes about the pattern that you tried
if you want to only match, you can omit the capture group
e* matches 0+ times an e char
the part .*?(?=[&,""]) matches as least chars until it can assert eiter & , or " to the right, so the positive lookahead expects a single char to the right to be present
You could shorten the pattern to a match only, using a negated character class that matches 0+ times any character except a whitespace char or &
myvalue=[^&\s]*
Regex demo
function regex(data) {
var test = data.match(/=(.*)&/);
if (test === null) {
return data.split('=')[1]
} else {
return test[1]
}
}
console.log(regex('abcdmyvalue=123&3e')); //123
console.log(regex('abcdmyvalue=123')); //123
here is your working code if there is no & at end of string it will have null and will go else block there we can simply split the string and get the value, If & is present at the end of string then regex will simply extract the value between = and &
if you want to use existing regex then you can do it like that
var test = data1.match(/=(.*)&|=(.*)/)
const result = test[1] ? test[1] : test[2];
console.log(result);
I need to format the price string in dart.
String can be: ₹ 2,19,990.00
String can be: $1,114.99
String can be: $14.99
What I tried:
void main() {
String str = "₹ 2,19,990.00";
RegExp regexp = RegExp("(\\d+[,.]?[\\d]*)");
RegExpMatch? match = regexp.firstMatch(str);
str = match!.group(1)!;
print(str);
}
What my output is: 2,19
What my output is: 1,114
What my output is: 14.99
Expected output: 219990.00
Expected output: 1114.99
Expected output: 14.99 (This one is correct because there is no comma)
The simplest solution would be to replace all non-digit/non-dot characters with nothing.
The most efficient way to do that is:
final re = RegExp(r"[^\d.]+");
String sanitizeCurrency(String input) => input.replaceAll(re, "");
You can't do it by matching because a match is always contiguous in the source string, and you want to omit the embedded ,s.
You can use this regex for search:
^\D+|(?<=\d),(?=\d)
And replace with an empty string i.e. "".
RegEx Details:
^: Start
\D+: Match 1+ non-digit characters
|: OR
(?<=\d),(?=\d): Match a comma if it surrounded with digits on both sides
RegEx Demo
Code: Using replaceAll method:
str = str.replaceAll(RegExp(r'^\D+|(?<=\d),(?=\d)'), '');
I would like to grab the first 4 characters of two words using RegEx. I have some RegEx experinece however a search did not yeild any results.
So if I have Awesome Sauce I would like the end result to be AwesSauc
Use the Replace Text action with the following parameters:
Pattern: \W*\b(\p{L}{1,4})\w*\W*
Replacement text: $1
See the regex demo.
Pattern details:
\W* - 0+ non-word chars (trim from the left)
\b - a leading word boundary
(\p{L}{1,4}) - Group 1 (later referred to via $1 backreference) matching any 1 to 4 letters (incl. Unicode ones)
\w* - any 0+ word chars (to match the rest of the word)
\W* - 0+ non-word chars (trim from the right)
I think this RegEx should do the job
string pattern = #"\b\w{4}";
var text = "The quick brown fox jumps over the lazy dog";
Regex regex = new Regex(pattern);
var match = regex.Match(text);
while (match.Captures.Count != 0)
{
foreach (var capture in match.Captures)
{
Console.WriteLine(capture);
}
match = match.NextMatch();
}
// outputs:
// quic
// brow
// jump
// over
// lazy
Alternatively you could use patterns like:
\b\w{1,4} => The, quic, brow, fox, jump, over, the, lazy, dog
\b[\w|\d]{1,4} => would also match digits
Update:
added a full example for C# and modified the pattern slightly. Also added some alternative patterns.
one approach with Linq
var res = new string(input.Split().SelectMany((x => x.Where((y, i) => i < 4))).ToArray());
Try this expression
\b[a-zA-Z0-9]{1,4}
Using regex would in fact be more complex and totally unnecessary for this case. Just do it as either of the below.
var sentence = "Awesome Sau";
// With LINQ
var linqWay = string.Join("", sentence.Split(" ".ToCharArray(), options:StringSplitOptions.RemoveEmptyEntries).Select(x => x.Substring(0, Math.Min(4,x.Length))).ToArray());
// Without LINQ
var oldWay = new StringBuilder();
string[] words = sentence.Split(" ".ToCharArray(), options:StringSplitOptions.RemoveEmptyEntries);
foreach(var word in words) {
oldWay.Append(word.Substring(0, Math.Min(4, word.Length)));
}
Edit:
Updated code based on #Dai's comment. Math.Min check borrowed as is from his suggestion.
I am developing a windows application in C#. I have been searching for the solution to my problem in creating a Regex pattern. I want to create a Regex pattern matching the either of the following strings:
XD=(111111) XT=( 588.466)m3 YT=( .246)m3 G=( 3.6)V N=(X0000000000) M=(Y0000000000) O=(Z0000000000) Date=(06.01.01)Time=(00:54:55) Q=( .00)m3/hr
XD=(111 ) XT=( 588.466)m3 YT=( .009)m3 G=( 3.6)V N=(X0000000000) M=(Y0000000000) O=(Z0000000000) Date=(06.01.01)Time=(00:54:55) Q=( .00)m3/hr
The specific requirement is that I need all the values from the above given string which is a collection of key/value pairs. Also, would like to know the right approach (in terms of efficiency and performance) out of the two...Regex pattern matching or substring, for the above problem.
Thank you all in advance and let me know, if more details are required.
I don't know C#, so there probably is a better way to build a key/value array. I constructed a regex and handed it to RegexBuddy which generated the following code snippet:
StringCollection keyList = new StringCollection();
StringCollection valueList = new StringCollection();
StringCollection unitList = new StringCollection();
try {
Regex regexObj = new Regex(
#"(?<key>\b\w+) # Match an alphanumeric identifier
\s*=\s* # Match a = (optionally surrounded by whitespace)
\( # Match a (
\s* # Match optional whitespace
(?<value>[^()]+) # Match the value string (anything except parens)
\) # Match a )
(?<unit>[^\s=]+ # Match an optional unit (anything except = or space)
\b # which must end at a word boundary
(?!\s*=) # and not be an identifier (i. e. followed by =)
)? # and is optional, as mentioned.",
RegexOptions.IgnorePatternWhitespace);
Match matchResult = regexObj.Match(subjectString);
while (matchResult.Success) {
keyList.Add(matchResult.Groups["key"].Value);
valueList.Add(matchResult.Groups["value"].Value);
unitList.Add(matchResult.Groups["unit"].Value);
matchResult = matchResult.NextMatch();
}
Regex re=new Regex(#"(\w+)\=\(([\d\s\.]+)\)");
MatchCollection m=re.Matches(s);
m[0].Groups will have { XD=(111111), XD, 111111 }
m[1].Groups will have { XT=( 588.466), XT, 588.466 }
String[] rows = { "XD=(111111) XT=( 588.466)m3 YT=( .246)m3 G=( 3.6)V N=(X0000000000) M=(Y0000000000) O=(Z0000000000) Date=(06.01.01)Time=(00:54:55) Q=( .00)m3/hr",
"XD=(111 ) XT=( 588.466)m3 YT=( .009)m3 G=( 3.6)V N=(X0000000000) M=(Y0000000000) O=(Z0000000000) Date=(06.01.01)Time=(00:54:55) Q=( .00)m3/hr" };
foreach (String s in rows) {
MatchCollection Pair = Regex.Matches(s, #"
(\S+) # Match all non-whitespace before the = and store it in group 1
= # Match the =
(\([^)]+\S+) # Match the part in brackets and following non-whitespace after the = and store it in group 2
", RegexOptions.IgnorePatternWhitespace);
foreach (Match item in Pair) {
Console.WriteLine(item.Groups[1] + " => " + item.Groups[2]);
}
Console.WriteLine();
}
Console.ReadLine();
If you want to extract the units also then use this regex
#"(\S+)=(\([^)]+(\S+))
I added a set of brackets around it, then you will find the unit in item.Groups[3]
I have a string something like "[aaa][vad][adf]", i would like to use regex to capture the data in[], and chars in [] can be char and number and no length limit. I am regex noob, can anyone help me on this?
Thanks.
You can try something like this:
var data = "[asd][dfhg][asfsa243]";
var re = new Regex(#"\[([^\]]*)\]");
var matches = re.Matches(data);
for (int i = 0; i < matches.Count; i++ )
{
var m = matches[i];
Console.WriteLine(m.Groups[1]);
}
Console.ReadLine();
This outputs:
asd
dfhg
asfsa243
The regular expression \[([^\]]*)\] matches zero or more occurrences of a character that isn't the ] character and which is between a pair of square brackets ([ and ])
This regex might work for you:
\[(\w+)\]
That if you by char refers to word character
Here is my suggestion:
\[(\w+)\]
The charachter will be provided in the first group of the match, like this:
var regex = new Regex(#"\[([\w\d]*)\]");
MatchCollection matchCollection = regex.Matches(stringToTest);
foreach (Match match in matchCollection)
{
Debug.Print(match.Groups[0].Value);
}
Here are some good resources for building regex's
http://www.regexlib.com
http://regexpal.com/
Here is the regex for Alphanumeric:
^[a-zA-Z0-9]+$
Here's how to ensure there are 3:
/^([a-zA-Z0-9]){3}$/
You could try -
[^\[\]\W]+
var matches = System.Text.RegularExpressions.Regex.Matches("[aaa][vad][adf]",#"[^\[\]\W]+").Cast<Match>().Select(m => m.Value);
That should ignore any '[', ']' and non-word characters and would return 'aaa', 'vad' and 'adf' from your example string.