Regular Expr when not all matches are present - regex

I am wondering if there is a way to handle situations where there is not always a match for all groups. In my case i have a text which i am trying to parse but there is an element that does not have some elements so my pattern skips over some data which is not desired.
<FONT FACE="Arial,Helvetica" size=2>1260 CORONA POINTE STE 120<br/>CORONA, CA 92879<br/><br/></font></td></tr><tr valign="top"><td></td><td><FONT FACE="Arial,Helvetica" size=2>2124 MAIN ST STE 100<br/>HUNTINGTON BEACH, CA 92648<br/>00610922 Miller, David S - Branch/Division Manager<br><br/><br/></font></td></tr><tr valign="top"><td></td><td>
the pattern i am using is below and will only create one match
/<FONT FACE="Arial,Helvetica" size=2>(.*?)<br\/>(.*?)<br\/>.*?License_id=(\d*?)">.*?<\/A>(.*?)<br>/gm
if i use this pattern i will have 2 matches
/<FONT FACE="Arial,Helvetica" size=2>(.*?)<br\/>(.*?)<br\/>/gm
In my case the source of problem is that i am trying to match the License_id= as well as the name which is not avail in the first match.
so what i am looking for is a way to return an empty match or something so if a match is not present it will not offset my data
I am using JavaScript / NodeJS

This way is done in 2 or 3 steps.
It first gets the record, from a FONT tag to just before the next FONT tag.
Then it removes all the tags from the record by replacing with a newline.
That makes each content section that is left, a separate line.
It then splits the string on newline to get into an array.
The last 2 things are optional, take your pick.
var html = "<FONT FACE=\"Arial,Helvetica\" size=2>1260 CORONA POINTE STE 120<br/>CORONA, CA 92879<br/><br/></font></td></tr><tr valign=\"top\"><td></td><td><FONT FACE=\"Arial,Helvetica\" size=2>2124 MAIN ST STE 100<br/>HUNTINGTON BEACH, CA 92648<br/>00610922 Miller, David S - Branch/Division Manager<br><br/><br/></font></td></tr><tr valign=\"top\"><td></td><td>";
var rxTag = new RegExp( "(?:\\s*<(?:(?:(?:(script|style|object|embed|applet|noframes|noscript|noembed)(?:\\s+(?:\"[\\S\\s]*?\"|'[\\S\\s]*?'|(?:(?!/>)[^>])?)+)?\\s*>)[\\S\\s]*?</\\1\\s*(?=>))|(?:/?[\\w:]+\\s*/?)|(?:[\\w:]+\\s+(?:\"[\\S\\s]*?\"|'[\\S\\s]*?'|[^>]?)+\\s*/?)|\\?[\\S\\s]*?\\?|(?:!(?:(?:DOCTYPE[\\S\\s]*?)|(?:\\[CDATA\\[[\\S\\s]*?\\]\\])|(?:--[\\S\\s]*?--)|(?:ATTLIST[\\S\\s]*?)|(?:ENTITY[\\S\\s]*?)|(?:ELEMENT[\\S\\s]*?))))>\\s*)+", "g" );
var rxRecord = new RegExp( "<font(?:\"[\\S\\s]*?\"|'[\\S\\s]*?'|[^>]?)+>(?:(?!<font(?:\"[\\S\\s]*?\"|'[\\S\\s]*?'|[^>]?)+>)[\\S\\s])*", "gi");
var match;
while ( match = rxRecord.exec( html ) )
{
var rec = match[0];
var sData;
sData = rec.replace( rxTag, "\r\n" );
sData = sData.trim();
console.log( sData );
var ary = [];
ary = sData.split( /\r?\n/ );
console.log( ary );
}

Related

Jest cell name won't recognise regex [duplicate]

I want to add a (variable) tag to values with regex, the pattern works fine with PHP but I have troubles implementing it into JavaScript.
The pattern is (value is the variable):
/(?!(?:[^<]+>|[^>]+<\/a>))\b(value)\b/is
I escaped the backslashes:
var str = $("#div").html();
var regex = "/(?!(?:[^<]+>|[^>]+<\\/a>))\\b(" + value + ")\\b/is";
$("#div").html(str.replace(regex, "" + value + ""));
But this seem not to be right, I logged the pattern and its exactly what it should be.
Any ideas?
To create the regex from a string, you have to use JavaScript's RegExp object.
If you also want to match/replace more than one time, then you must add the g (global match) flag. Here's an example:
var stringToGoIntoTheRegex = "abc";
var regex = new RegExp("#" + stringToGoIntoTheRegex + "#", "g");
// at this point, the line above is the same as: var regex = /#abc#/g;
var input = "Hello this is #abc# some #abc# stuff.";
var output = input.replace(regex, "!!");
alert(output); // Hello this is !! some !! stuff.
JSFiddle demo here.
In the general case, escape the string before using as regex:
Not every string is a valid regex, though: there are some speciall characters, like ( or [. To work around this issue, simply escape the string before turning it into a regex. A utility function for that goes in the sample below:
function escapeRegExp(stringToGoIntoTheRegex) {
return stringToGoIntoTheRegex.replace(/[-\/\\^$*+?.()|[\]{}]/g, '\\$&');
}
var stringToGoIntoTheRegex = escapeRegExp("abc"); // this is the only change from above
var regex = new RegExp("#" + stringToGoIntoTheRegex + "#", "g");
// at this point, the line above is the same as: var regex = /#abc#/g;
var input = "Hello this is #abc# some #abc# stuff.";
var output = input.replace(regex, "!!");
alert(output); // Hello this is !! some !! stuff.
JSFiddle demo here.
Note: the regex in the question uses the s modifier, which didn't exist at the time of the question, but does exist -- a s (dotall) flag/modifier in JavaScript -- today.
If you are trying to use a variable value in the expression, you must use the RegExp "constructor".
var regex = "(?!(?:[^<]+>|[^>]+<\/a>))\b(" + value + ")\b";
new RegExp(regex, "is")
I found I had to double slash the \b to get it working. For example to remove "1x" words from a string using a variable, I needed to use:
str = "1x";
var regex = new RegExp("\\b"+str+"\\b","g"); // same as inv.replace(/\b1x\b/g, "")
inv=inv.replace(regex, "");
You don't need the " to define a regular expression so just:
var regex = /(?!(?:[^<]+>|[^>]+<\/a>))\b(value)\b/is; // this is valid syntax
If value is a variable and you want a dynamic regular expression then you can't use this notation; use the alternative notation.
String.replace also accepts strings as input, so you can do "fox".replace("fox", "bear");
Alternative:
var regex = new RegExp("/(?!(?:[^<]+>|[^>]+<\/a>))\b(value)\b/", "is");
var regex = new RegExp("/(?!(?:[^<]+>|[^>]+<\/a>))\b(" + value + ")\b/", "is");
var regex = new RegExp("/(?!(?:[^<]+>|[^>]+<\/a>))\b(.*?)\b/", "is");
Keep in mind that if value contains regular expressions characters like (, [ and ? you will need to escape them.
I found this thread useful - so I thought I would add the answer to my own problem.
I wanted to edit a database configuration file (datastax cassandra) from a node application in javascript and for one of the settings in the file I needed to match on a string and then replace the line following it.
This was my solution.
dse_cassandra_yaml='/etc/dse/cassandra/cassandra.yaml'
// a) find the searchString and grab all text on the following line to it
// b) replace all next line text with a newString supplied to function
// note - leaves searchString text untouched
function replaceStringNextLine(file, searchString, newString) {
fs.readFile(file, 'utf-8', function(err, data){
if (err) throw err;
// need to use double escape '\\' when putting regex in strings !
var re = "\\s+(\\-\\s(.*)?)(?:\\s|$)";
var myRegExp = new RegExp(searchString + re, "g");
var match = myRegExp.exec(data);
var replaceThis = match[1];
var writeString = data.replace(replaceThis, newString);
fs.writeFile(file, writeString, 'utf-8', function (err) {
if (err) throw err;
console.log(file + ' updated');
});
});
}
searchString = "data_file_directories:"
newString = "- /mnt/cassandra/data"
replaceStringNextLine(dse_cassandra_yaml, searchString, newString );
After running, it will change the existing data directory setting to the new one:
config file before:
data_file_directories:
- /var/lib/cassandra/data
config file after:
data_file_directories:
- /mnt/cassandra/data
Much easier way: use template literals.
var variable = 'foo'
var expression = `.*${variable}.*`
var re = new RegExp(expression, 'g')
re.test('fdjklsffoodjkslfd') // true
re.test('fdjklsfdjkslfd') // false
Using string variable(s) content as part of a more complex composed regex expression (es6|ts)
This example will replace all urls using my-domain.com to my-other-domain (both are variables).
You can do dynamic regexs by combining string values and other regex expressions within a raw string template. Using String.raw will prevent javascript from escaping any character within your string values.
// Strings with some data
const domainStr = 'my-domain.com'
const newDomain = 'my-other-domain.com'
// Make sure your string is regex friendly
// This will replace dots for '\'.
const regexUrl = /\./gm;
const substr = `\\\.`;
const domain = domainStr.replace(regexUrl, substr);
// domain is a regex friendly string: 'my-domain\.com'
console.log('Regex expresion for domain', domain)
// HERE!!! You can 'assemble a complex regex using string pieces.
const re = new RegExp( String.raw `([\'|\"]https:\/\/)(${domain})(\S+[\'|\"])`, 'gm');
// now I'll use the regex expression groups to replace the domain
const domainSubst = `$1${newDomain}$3`;
// const page contains all the html text
const result = page.replace(re, domainSubst);
note: Don't forget to use regex101.com to create, test and export REGEX code.
var string = "Hi welcome to stack overflow"
var toSearch = "stack"
//case insensitive search
var result = string.search(new RegExp(toSearch, "i")) > 0 ? 'Matched' : 'notMatched'
https://jsfiddle.net/9f0mb6Lz/
Hope this helps

How do I use the 1st character match using ^ in GAS?

I am trying to match the 1st character using regex in GAS. When I insert ^, the code doesn't work.If my id is "DEL", then I need words starting with "D", when id is "DEL" then all words strarting with "DEL".
function getAirportMatch(e) {
var airportlist = "`DELHI VIDP, MINDELIHM HEID, DELHI VIDD, LIHELD HDEL";
var id = "DEL";
var regExp = new RegExp("^(?:"+id+")","gm"); // "i" is for case insensitive
var airport = regExp.exec(airportlist);
Logger.log(airport);````
To match terms starting with something, use word boundary \b and matching everything up to the next comma (or end, which ever comes first):
"\b"+id+"[^,]*"
If you simply want to see which airport names start with DEL you can simply make use of the startsWith method:
var airportlist = "DELHI VIDP, MINDELIHM HEID, DELHI VIDD, LIHELD HDEL";
var airportarray = airportlist.split(', ');
var id = "DEL";
airportarray.forEach(e => {if (e.startsWith(id.toString()))console.log(e)})
The snippet above creates an array with all the airport names and then checks if any of them start with the id you have supplied.
Reference
String.prototype.startsWith().

Regex for characters in specific location in string

Using notepad++, how can I replace the -s noted by the carats? The dashes I want to replace occurs every 7th character in the string.
11.871-2-2.737-2.00334-2
^ ^ ^
123456781234567812345678
It's pretty simple since it's only dashes:
(\S*?)-
Begin capture group.............................. (
Find any number of non-space chars... \S*
Lazily until...............................................?
End capture group...................................)
No capture find hyphen...........................-
Demo 1
var str = `11.871-2-2.737-2.00334-2`;
var sub = `$1`;
var rgx = /(\S*?)-/g;
var res = str.replace(rgx, sub);
console.log(res);
"There is a dash (right above 1) that I would like to preserve. This seems to get rid of all the dashes in the string"
The question clearly shows that there isn't a dash at the "1 position", but since there's a possibility that it's possible considering the pattern (n7). Don't have time to break it down, but I can refer you to a proper definition of the meta char \b.
Demo 2
var str = `-11.871-2-2.737-2.00334-2`;
var sub = `$1$2`;
var rgx = /\b[-]{1}(\S*?)-(\S*?)\b/g;
var res = str.replace(rgx, sub);
console.log(res);
Search for ([0-9\.-]{6,6})-
Replace with: $1MY_SEPARATOR

Regex that will extract the string between two known strings [duplicate]

I want to match a portion of a string using a regular expression and then access that parenthesized substring:
var myString = "something format_abc"; // I want "abc"
var arr = /(?:^|\s)format_(.*?)(?:\s|$)/.exec(myString);
console.log(arr); // Prints: [" format_abc", "abc"] .. so far so good.
console.log(arr[1]); // Prints: undefined (???)
console.log(arr[0]); // Prints: format_undefined (!!!)
What am I doing wrong?
I've discovered that there was nothing wrong with the regular expression code above: the actual string which I was testing against was this:
"date format_%A"
Reporting that "%A" is undefined seems a very strange behaviour, but it is not directly related to this question, so I've opened a new one, Why is a matched substring returning "undefined" in JavaScript?.
The issue was that console.log takes its parameters like a printf statement, and since the string I was logging ("%A") had a special value, it was trying to find the value of the next parameter.
Update: 2019-09-10
The old way to iterate over multiple matches was not very intuitive. This lead to the proposal of the String.prototype.matchAll method. This new method is in the ECMAScript 2020 specification. It gives us a clean API and solves multiple problems. It is in major browsers and JS engines since Chrome 73+ / Node 12+ and Firefox 67+.
The method returns an iterator and is used as follows:
const string = "something format_abc";
const regexp = /(?:^|\s)format_(.*?)(?:\s|$)/g;
const matches = string.matchAll(regexp);
for (const match of matches) {
console.log(match);
console.log(match.index)
}
As it returns an iterator, we can say it's lazy, this is useful when handling particularly large numbers of capturing groups, or very large strings. But if you need, the result can be easily transformed into an Array by using the spread syntax or the Array.from method:
function getFirstGroup(regexp, str) {
const array = [...str.matchAll(regexp)];
return array.map(m => m[1]);
}
// or:
function getFirstGroup(regexp, str) {
return Array.from(str.matchAll(regexp), m => m[1]);
}
In the meantime, while this proposal gets more wide support, you can use the official shim package.
Also, the internal workings of the method are simple. An equivalent implementation using a generator function would be as follows:
function* matchAll(str, regexp) {
const flags = regexp.global ? regexp.flags : regexp.flags + "g";
const re = new RegExp(regexp, flags);
let match;
while (match = re.exec(str)) {
yield match;
}
}
A copy of the original regexp is created; this is to avoid side-effects due to the mutation of the lastIndex property when going through the multple matches.
Also, we need to ensure the regexp has the global flag to avoid an infinite loop.
I'm also happy to see that even this StackOverflow question was referenced in the discussions of the proposal.
original answer
You can access capturing groups like this:
var myString = "something format_abc";
var myRegexp = /(?:^|\s)format_(.*?)(?:\s|$)/g;
var myRegexp = new RegExp("(?:^|\s)format_(.*?)(?:\s|$)", "g");
var matches = myRegexp.exec(myString);
console.log(matches[1]); // abc
And if there are multiple matches you can iterate over them:
var myString = "something format_abc";
var myRegexp = new RegExp("(?:^|\s)format_(.*?)(?:\s|$)", "g");
match = myRegexp.exec(myString);
while (match != null) {
// matched text: match[0]
// match start: match.index
// capturing group n: match[n]
console.log(match[0])
match = myRegexp.exec(myString);
}
Here’s a method you can use to get the n​th capturing group for each match:
function getMatches(string, regex, index) {
index || (index = 1); // default to the first capturing group
var matches = [];
var match;
while (match = regex.exec(string)) {
matches.push(match[index]);
}
return matches;
}
// Example :
var myString = 'something format_abc something format_def something format_ghi';
var myRegEx = /(?:^|\s)format_(.*?)(?:\s|$)/g;
// Get an array containing the first capturing group for every match
var matches = getMatches(myString, myRegEx, 1);
// Log results
document.write(matches.length + ' matches found: ' + JSON.stringify(matches))
console.log(matches);
var myString = "something format_abc";
var arr = myString.match(/\bformat_(.*?)\b/);
console.log(arr[0] + " " + arr[1]);
The \b isn't exactly the same thing. (It works on --format_foo/, but doesn't work on format_a_b) But I wanted to show an alternative to your expression, which is fine. Of course, the match call is the important thing.
Last but not least, I found one line of code that worked fine for me (JS ES6):
let reg = /#([\S]+)/igm; // Get hashtags.
let string = 'mi alegría es total! ✌🙌\n#fiestasdefindeaño #PadreHijo #buenosmomentos #france #paris';
let matches = (string.match(reg) || []).map(e => e.replace(reg, '$1'));
console.log(matches);
This will return:
['fiestasdefindeaño', 'PadreHijo', 'buenosmomentos', 'france', 'paris']
In regards to the multi-match parentheses examples above, I was looking for an answer here after not getting what I wanted from:
var matches = mystring.match(/(?:neededToMatchButNotWantedInResult)(matchWanted)/igm);
After looking at the slightly convoluted function calls with while and .push() above, it dawned on me that the problem can be solved very elegantly with mystring.replace() instead (the replacing is NOT the point, and isn't even done, the CLEAN, built-in recursive function call option for the second parameter is!):
var yourstring = 'something format_abc something format_def something format_ghi';
var matches = [];
yourstring.replace(/format_([^\s]+)/igm, function(m, p1){ matches.push(p1); } );
After this, I don't think I'm ever going to use .match() for hardly anything ever again.
String#matchAll (see the Stage 3 Draft / December 7, 2018 proposal), simplifies acccess to all groups in the match object (mind that Group 0 is the whole match, while further groups correspond to the capturing groups in the pattern):
With matchAll available, you can avoid the while loop and exec with /g... Instead, by using matchAll, you get back an iterator which you can use with the more convenient for...of, array spread, or Array.from() constructs
This method yields a similar output to Regex.Matches in C#, re.finditer in Python, preg_match_all in PHP.
See a JS demo (tested in Google Chrome 73.0.3683.67 (official build), beta (64-bit)):
var myString = "key1:value1, key2-value2!!#key3=value3";
var matches = myString.matchAll(/(\w+)[:=-](\w+)/g);
console.log([...matches]); // All match with capturing group values
The console.log([...matches]) shows
You may also get match value or specific group values using
let matchData = "key1:value1, key2-value2!!#key3=value3".matchAll(/(\w+)[:=-](\w+)/g)
var matches = [...matchData]; // Note matchAll result is not re-iterable
console.log(Array.from(matches, m => m[0])); // All match (Group 0) values
// => [ "key1:value1", "key2-value2", "key3=value3" ]
console.log(Array.from(matches, m => m[1])); // All match (Group 1) values
// => [ "key1", "key2", "key3" ]
NOTE: See the browser compatibility details.
Terminology used in this answer:
Match indicates the result of running your RegEx pattern against your string like so: someString.match(regexPattern).
Matched patterns indicate all matched portions of the input string, which all reside inside the match array. These are all instances of your pattern inside the input string.
Matched groups indicate all groups to catch, defined in the RegEx pattern. (The patterns inside parentheses, like so: /format_(.*?)/g, where (.*?) would be a matched group.) These reside within matched patterns.
Description
To get access to the matched groups, in each of the matched patterns, you need a function or something similar to iterate over the match. There are a number of ways you can do this, as many of the other answers show. Most other answers use a while loop to iterate over all matched patterns, but I think we all know the potential dangers with that approach. It is necessary to match against a new RegExp() instead of just the pattern itself, which only got mentioned in a comment. This is because the .exec() method behaves similar to a generator function – it stops every time there is a match, but keeps its .lastIndex to continue from there on the next .exec() call.
Code examples
Below is an example of a function searchString which returns an Array of all matched patterns, where each match is an Array with all the containing matched groups. Instead of using a while loop, I have provided examples using both the Array.prototype.map() function as well as a more performant way – using a plain for-loop.
Concise versions (less code, more syntactic sugar)
These are less performant since they basically implement a forEach-loop instead of the faster for-loop.
// Concise ES6/ES2015 syntax
const searchString =
(string, pattern) =>
string
.match(new RegExp(pattern.source, pattern.flags))
.map(match =>
new RegExp(pattern.source, pattern.flags)
.exec(match));
// Or if you will, with ES5 syntax
function searchString(string, pattern) {
return string
.match(new RegExp(pattern.source, pattern.flags))
.map(match =>
new RegExp(pattern.source, pattern.flags)
.exec(match));
}
let string = "something format_abc",
pattern = /(?:^|\s)format_(.*?)(?:\s|$)/;
let result = searchString(string, pattern);
// [[" format_abc", "abc"], null]
// The trailing `null` disappears if you add the `global` flag
Performant versions (more code, less syntactic sugar)
// Performant ES6/ES2015 syntax
const searchString = (string, pattern) => {
let result = [];
const matches = string.match(new RegExp(pattern.source, pattern.flags));
for (let i = 0; i < matches.length; i++) {
result.push(new RegExp(pattern.source, pattern.flags).exec(matches[i]));
}
return result;
};
// Same thing, but with ES5 syntax
function searchString(string, pattern) {
var result = [];
var matches = string.match(new RegExp(pattern.source, pattern.flags));
for (var i = 0; i < matches.length; i++) {
result.push(new RegExp(pattern.source, pattern.flags).exec(matches[i]));
}
return result;
}
let string = "something format_abc",
pattern = /(?:^|\s)format_(.*?)(?:\s|$)/;
let result = searchString(string, pattern);
// [[" format_abc", "abc"], null]
// The trailing `null` disappears if you add the `global` flag
I have yet to compare these alternatives to the ones previously mentioned in the other answers, but I doubt this approach is less performant and less fail-safe than the others.
Your syntax probably isn't the best to keep. FF/Gecko defines RegExp as an extension of Function.
(FF2 went as far as typeof(/pattern/) == 'function')
It seems this is specific to FF -- IE, Opera, and Chrome all throw exceptions for it.
Instead, use either method previously mentioned by others: RegExp#exec or String#match.
They offer the same results:
var regex = /(?:^|\s)format_(.*?)(?:\s|$)/;
var input = "something format_abc";
regex(input); //=> [" format_abc", "abc"]
regex.exec(input); //=> [" format_abc", "abc"]
input.match(regex); //=> [" format_abc", "abc"]
There is no need to invoke the exec method! You can use "match" method directly on the string. Just don't forget the parentheses.
var str = "This is cool";
var matches = str.match(/(This is)( cool)$/);
console.log( JSON.stringify(matches) ); // will print ["This is cool","This is"," cool"] or something like that...
Position 0 has a string with all the results. Position 1 has the first match represented by parentheses, and position 2 has the second match isolated in your parentheses. Nested parentheses are tricky, so beware!
With es2018 you can now String.match() with named groups, makes your regex more explicit of what it was trying to do.
const url =
'https://stackoverflow.com/questions/432493/how-do-you-access-the-matched-groups-in-a-javascript-regular-expression?some=parameter';
const regex = /(?<protocol>https?):\/\/(?<hostname>[\w-\.]*)\/(?<pathname>[\w-\./]+)\??(?<querystring>.*?)?$/;
const { groups: segments } = url.match(regex);
console.log(segments);
and you'll get something like
{protocol: "https", hostname: "stackoverflow.com", pathname: "questions/432493/how-do-you-access-the-matched-groups-in-a-javascript-regular-expression", querystring: "some=parameter"}
A one liner that is practical only if you have a single pair of parenthesis:
while ( ( match = myRegex.exec( myStr ) ) && matches.push( match[1] ) ) {};
Using your code:
console.log(arr[1]); // prints: abc
console.log(arr[0]); // prints: format_abc
Edit: Safari 3, if it matters.
function getMatches(string, regex, index) {
index || (index = 1); // default to the first capturing group
var matches = [];
var match;
while (match = regex.exec(string)) {
matches.push(match[index]);
}
return matches;
}
// Example :
var myString = 'Rs.200 is Debited to A/c ...2031 on 02-12-14 20:05:49 (Clear Bal Rs.66248.77) AT ATM. TollFree 1800223344 18001024455 (6am-10pm)';
var myRegEx = /clear bal.+?(\d+\.?\d{2})/gi;
// Get an array containing the first capturing group for every match
var matches = getMatches(myString, myRegEx, 1);
// Log results
document.write(matches.length + ' matches found: ' + JSON.stringify(matches))
console.log(matches);
function getMatches(string, regex, index) {
index || (index = 1); // default to the first capturing group
var matches = [];
var match;
while (match = regex.exec(string)) {
matches.push(match[index]);
}
return matches;
}
// Example :
var myString = 'something format_abc something format_def something format_ghi';
var myRegEx = /(?:^|\s)format_(.*?)(?:\s|$)/g;
// Get an array containing the first capturing group for every match
var matches = getMatches(myString, myRegEx, 1);
// Log results
document.write(matches.length + ' matches found: ' + JSON.stringify(matches))
console.log(matches);
Your code works for me (FF3 on Mac) even if I agree with PhiLo that the regex should probably be:
/\bformat_(.*?)\b/
(But, of course, I'm not sure because I don't know the context of the regex.)
As #cms said in ECMAScript (ECMA-262) you can use matchAll. It return an iterator and by putting it in [... ] (spread operator) it converts to an array.(this regex extract urls of file names)
let text = `File1 File2`;
let fileUrls = [...text.matchAll(/href="(http\:\/\/[^"]+\.\w{3})\"/g)].map(r => r[1]);
console.log(fileUrls);
/*Regex function for extracting object from "window.location.search" string.
*/
var search = "?a=3&b=4&c=7"; // Example search string
var getSearchObj = function (searchString) {
var match, key, value, obj = {};
var pattern = /(\w+)=(\w+)/g;
var search = searchString.substr(1); // Remove '?'
while (match = pattern.exec(search)) {
obj[match[0].split('=')[0]] = match[0].split('=')[1];
}
return obj;
};
console.log(getSearchObj(search));
You don't really need an explicit loop to parse multiple matches — pass a replacement function as the second argument as described in: String.prototype.replace(regex, func):
var str = "Our chief weapon is {1}, {0} and {2}!";
var params= ['surprise', 'fear', 'ruthless efficiency'];
var patt = /{([^}]+)}/g;
str=str.replace(patt, function(m0, m1, position){return params[parseInt(m1)];});
document.write(str);
The m0 argument represents the full matched substring {0}, {1}, etc. m1 represents the first matching group, i.e. the part enclosed in brackets in the regex which is 0 for the first match. And position is the starting index within the string where the matching group was found — unused in this case.
We can access the matched group in a regular expressions by using backslash followed by number of the matching group:
/([a-z])\1/
In the code \1 represented matched by first group ([a-z])
I you are like me and wish regex would return an Object like this:
{
match: '...',
matchAtIndex: 0,
capturedGroups: [ '...', '...' ]
}
then snip the function from below
/**
* #param {string | number} input
* The input string to match
* #param {regex | string} expression
* Regular expression
* #param {string} flags
* Optional Flags
*
* #returns {array}
* [{
match: '...',
matchAtIndex: 0,
capturedGroups: [ '...', '...' ]
}]
*/
function regexMatch(input, expression, flags = "g") {
let regex = expression instanceof RegExp ? expression : new RegExp(expression, flags)
let matches = input.matchAll(regex)
matches = [...matches]
return matches.map(item => {
return {
match: item[0],
matchAtIndex: item.index,
capturedGroups: item.length > 1 ? item.slice(1) : undefined
}
})
}
let input = "key1:value1, key2:value2 "
let regex = /(\w+):(\w+)/g
let matches = regexMatch(input, regex)
console.log(matches)
One line solution:
const matches = (text,regex) => [...text.matchAll(regex)].map(([match])=>match)
So you can use this way (must use /g):
matches("something format_abc", /(?:^|\s)format_(.*?)(?:\s|$)/g)
result:
[" format_abc"]
JUST USE RegExp.$1...$n th group
eg:
1.To match 1st group RegExp.$1
To match 2nd group RegExp.$2
if you use 3 group in regex likey(note use after string.match(regex))
RegExp.$1 RegExp.$2 RegExp.$3
var str = "The rain in ${india} stays safe";
var res = str.match(/\${(.*?)\}/ig);
//i used only one group in above example so RegExp.$1
console.log(RegExp.$1)
//easiest way is use RegExp.$1 1st group in regex and 2nd grounp like
//RegExp.$2 if exist use after match
var regex=/\${(.*?)\}/ig;
var str = "The rain in ${SPAIN} stays ${mainly} in the plain";
var res = str.match(regex);
for (const match of res) {
var res = match.match(regex);
console.log(match);
console.log(RegExp.$1)
}
Get all group occurrence
let m=[], s = "something format_abc format_def format_ghi";
s.replace(/(?:^|\s)format_(.*?)(?:\s|$)/g, (x,y)=> m.push(y));
console.log(m);
I thought you just want to grab all the words containing the abc substring and store the matched group/entries, so I made this script:
s = 'something format_abc another word abc abc_somestring'
console.log(s.match(/\b\w*abc\w*\b/igm));
\b - a word boundary
\w* - 0+ word chars
abc - your exact match
\w* - 0+ word chars
\b - a word boundary
References: Regex: Match all the words that contains some word
https://javascript.info/regexp-introduction

Google sheet : REGEXREPLACE match everything except a particular pattern

I would try to replace everything inside this string :
[JGMORGAN - BANK2] n° 10 NEWYORK, n° 222 CAEN, MONTELLIER, VANNES / TARARTA TIs
1303222074, 1403281851 & 1307239335 et Cloture TIs 1403277567,
1410315029
Except the following numbers :
1303222074
1403281851
1307239335
1403277567
1410315029
I have built a REGEX to match them :
1[0-9]{9}
But I have not figured it out to do the opposite that is everything except all matches ...
google spreadsheet use the Re2 regex engine and doesn't support many usefull features that can help you to do that. So a basic workaround can help you:
match what you want to preserve first and capture it:
pattern: [0-9]*(?:[0-9]{0,9}[^0-9]+)*(?:([0-9]{9,})|[0-9]*\z)
replacement: $1 (with a space after)
demo
So probably something like this:
=TRIM(REGEXREPLACE("[JGMORGAN - BANK2] n° 10 NEWYORK, n° 222 CAEN, MONTELLIER, VANNES / TARARTA TIs 1303222074, 1403281851 & 1307239335 et Cloture TIs 1403277567, 1410315029"; "[0-9]*(?:[0-9]{0,9}[^0-9]+)*(?:([0-9]{9,})|[0-9]*\z)"; "$1 "))
You can also do this with dynamic native functions:
=REGEXEXTRACT(A1,rept("(\d{10}).*",counta(split(regexreplace(A1,"\d{10}","#"),"#"))-1))
basically it is first split by the desired string, to figure out how many occurrences there are of it, then repeats the regex to dynamically create that number of capture groups, thus leaving you in the end with only those values.
First of all thank you Casimir for your help. It gave me an idea that will not be possible with a built-in functions and strong regex lol.
I found out that I can make a homemade function for my own purposes (yes I'm not very "up to date").
It's not very well coded and it returns doublons. But rather than fixing it properly, I use the built in UNIQUE() function on top of if to get rid of them; it's ugly and I'm lazy but it does the job, that is, a list of all matches of on specific regex (which is: 1[0-9]{9}). Here it is:
function ti_extract(input) {
var tab_tis = new Array();
var tab_strings = new Array();
tab_tis.push(input.match(/1[0-9]{9}/)); // get the TI and insert in tab_tis
var string_modif = input.replace(tab_tis[0], " "); // modify source string (remove everything except the TI)
tab_strings.push(string_modif); // insert this new string in the table
var v = 0;
var patt = new RegExp(/1[0-9]{9}/);
var fin = patt.test(tab_strings[v]);
var first_string = tab_strings[v];
do {
first_string = tab_strings[v]; // string 0, or the string with the first removed TI
tab_tis.push(first_string.match(/1[0-9]{9}/)); // analyze the string and get the new TI to put it in the table
var string_modif2 = first_string.replace(tab_tis[v], " "); // modify the string again to remove the new TI from the old string
tab_strings.push(string_modif2);
v += 1;
}
while(v < 15)
return tab_tis;
}