I want to create a regex that match '.', '#' and ':' and also match everything inside these brackets '[' & ']' such as [foo] & [bar]
I already have this match string.match(/[.#:]/g) for '.','#' and ':'.
I know that the brackets regex should look like this \[.\]
but how do I combine them both to one condition?
thanks,
Alon
to combine them use
/[.#:]|(?:\[.+?\])/g
?: is optional and is used to not capture the group (anything in parenthesis)
UPDATE:
.+? (one or more) or .*?(for zero or more)- use this for lazy matching, otherwise [ sdfsdf][sdfsddf ] will be matched
var s = "a . b # c : d [foo]";
var m = /[.:#]|\[.*?\]/g;
s.match(m);
// returns [".", "#", ":", "[foo]"]
var data = '[content]kjalksdjfa.sdf[sc.tt].#:';
var myregexp = /(\[.+?\])|[.#:]/g;
var match = myregexp.exec(data);
var result = "Matches:\n";
while (match != null) {
result += "match:"+match[0] + ',\n';
match = myregexp.exec(data);
}
alert(result);
Related
I’d would to replace all “?” by “&” except the first one by javascript. I found some regular expressions but they didn’t work.
I have something like:
home/?a=1
home/?a=1?b=2
home/?a=1?b=2?c=3
And I would like:
home/?a=1
home/?a=1&b=2
home/?a=1&b=2&c=3
Someone know how to I can do it?
Thanks!
I don't think it's possible with regex but you can split the string and then join it back together, manually replacing the first occurance:
var split = 'home/?a=1?b=2'.split('?'); // [ 'home/', 'a=1', 'b=2' ]
var replaced = split[0] + '?' + split.slice(1).join('&') // 'home/?a=1&b=2'
console.log(replaced);
You could match from the start of the string not a question mark using a negated character class [^?]+ followed by matching a question mark and capture that in the first capturing group. In the second capturing group capture the rest of the string.
Use replace and pass a function as the second parameter where you return the first capturing group followed by the second capturing group where all the question marks are replaced by &
let strings = [
"home/?a=1",
"home/?a=1?b=2",
"home/?a=1?b=2?c=3"
];
strings.forEach((str) => {
let result = str.replace(/(^[^?]+\?)(.*)/, function(match, group1, group2) {
return group1 + group2.replace(/\?/g, '&')
});
console.log(result);
});
You can split it by "?" and then rewrap the array:
var string = "home/?a=1?b=2";
var str = string.split('?');
var new = str[0] + '?'; // text before first '?' and first '?'
for( var x = 1; x < str.length; x++ ) {
new = new + str[x];
if( x != ( str.length - 1 ) ) new = new + '&'; //to avoid place a '&' after the string
}
You can use /([^\/])\?/ as pattern in regex that match any ? character that isn't after / character.
var str = str.replace(/([^\/])\?/g, "$1&");
var str = "home/?a=1\nhome/?a=1?b=2\nhome/?a=1?b=2?c=3\n".replace(/([^\/])\?/g, "$1&");
console.log(str);
I have a log like
t=2016-08-03T18:47:26+0000 lvl=dbug msg="Event Received" Service=SomeService
and I want to turn it into a javascript object like
{
t: 2016-08-03T18:47:26+0000,
lvl: dbug
msg: "Event Received"
Service: SomeService
}
But I am having trouble coming up with a regex that will detect the string "Event Received" in the log line.
I want to split the log line by space but because of the string it is much more difficult.
I am trying to come up with a regex that will detect the fields and parameters so that I can isolate them and split with the equal sign.
I suggest a regex without any lookahead:
var re = /(\w+)=(?:"([^"]*)"|(\S*))/g;
See the regex demo
The point is that the first group ((\w+)) captures the attribute name and the 2nd and 3rd are placed into a non-capturing "container" as alternative branches. Their values can be checked and then either one will be used to fill out the object.
Pattern details:
(\w+) - Group 1 (attribute name) matching 1+ word chars (from [a-zA-Z0-9_] ranges)
= - an equal sign
(?:"([^"]*)"|(\S*)) - a non-capturing "container" group matching either of the two alternatives:
"([^"]*)" - a quote, then Group 2 capturing 0+ chars other than ", and a quote
| - or
(\S*) - Group 3 capturing 0+ non-whitespace symbols.
var rx = /(\w+)=(?:"([^"]*)"|(\S*))/g;
var s = "t=2016-08-03T18:47:26+0000 lvl=dbug msg=\"Event Received\" Service=SomeService";
var obj = {};
while((m=rx.exec(s))!==null) {
if (m[2]) {
obj[m[1]] = m[2];
} else {
obj[m[1]] = m[3];
}
}
console.log(obj);
You can use this regex to capture various name=value pairs:
/(\w+)=(.*?)(?= \w+=|$)/gm
RegEx Demo
Code:
var re = /(\w+)=(.*?)(?= \w+=|$)/gm;
var str = 't=2016-08-03T18:47:26+0000 lvl=dbug msg="Event Received" Service=SomeService';
var m;
var result = {};
while ((m = re.exec(str)) !== null) {
if (m.index === re.lastIndex)
re.lastIndex++;
result[m[1]] = m[2];
}
console.log(result);
Use this pattern:
/^t=([^ ]+) lvl=([^ ]+) msg=(.*?[a-z]") Service=(.*)$/gm
Online Demo
To achieve expected result, use below
var x = 't=2016-08-03T18:47:26+0000 lvl=dbug msg="Event Received" Service=SomeService';
var y = x.replace(/=/g,':').split(' ');
var z = '{'+ y+'}';
console.log(z);
http://codepen.io/nagasai/pen/oLPRAy
I have a JS regex match that seems to include the brackets incorrectly. I tested it out at Regex101 and it seems to work appropriately there but when I run it I get this alert response:
[#],[Type,' '],[Problem w/ICD],['- ',Assessment],[' : ',Comment],[LF],[LF]
var temp = "[#]. [Type,' '][Problem w/ICD]['- ',Assessment][' : ',Comment][LF][LF]";
var rep = temp.match(/\[(.*?)\]/g);
alert(rep);
Why are the brackets included when they are outside the capture group?
The brackets are included because when using string#match and a regex with /g modifier, you will lose capturing groups.
If the regular expression includes the g flag, the method returns an Array containing all matched substrings rather than match objects. Captured groups are not returned.
You need to use a RegExp#exec() in a loop, and access the first capturing group via index 1.
var re = /\[(.*?)\]/g;
var str = '[#]. [Type,\' \'][Problem w/ICD][\'- \',Assessment][\' : \',Comment][LF][LF]';
var m;
var res = [];
while ((m = re.exec(str)) !== null) {
res.push(m[1]);
}
console.log(res);
Result:
["#", "Type,' '", "Problem w/ICD", "'- ',Assessment", "' : ',Comment", "LF", "LF"]
I'm struggling with a regex for Javascript.
Here is a string from which I want to match all words but the one prefixed by \+\s and suffixed by \s\+ :
this-is my + crappy + example
The regex should match :
this-is my + crappy + example
match 1: this-is
match 2: my
match 3: example
You can use the alternation operator in context placing what you want to exclude on the left, ( saying throw this away, it's garbage ) and place what you want to match in a capturing group on the right side.
\+[^+]+\+|([\w-]+)
Example:
var re = /\+[^+]+\+|([\w-]+)/g,
s = "this-is my + crappy + example",
match,
results = [];
while (match = re.exec(s)) {
results.push(match[1]);
}
console.log(results.filter(Boolean)) //=> [ 'this-is', 'my', 'example' ]
Alternatively, you could replace between the + characters and then match your words.
var s = 'this-is my + crappy + example',
r = s.replace(/\+[^+]*\+/g, '').match(/[\w-]+/g)
console.log(r) //=> [ 'this-is', 'my', 'example' ]
As per desired output. Get the matched group from index 1.
([\w-]+)|\+\s\w+\s\+
Live DEMO
MATCH 1 this-is
MATCH 2 my
MATCH 3 example
text = '#container a.filter(.top).filter(.bottom).filter(.middle)';
regex = /(.*?)\.filter\((.*?)\)/;
matches = text.match(regex);
log(matches);
// matches[1] is '#container a'
//matchss[2] is '.top'
I expect to capture
matches[1] is '#container a'
matches[2] is '.top'
matches[3] is '.bottom'
matches[4] is '.middle'
One solution would be to split the string into #container a and rest. Then take rest and execute recursive exec to get item inside ().
Update: I am posting a solution that does work. However I am looking for a better solution. Don't really like the idea of splitting the string and then processing
Here is a solution that works.
matches = [];
var text = '#container a.filter(.top).filter(.bottom).filter(.middle)';
var regex = /(.*?)\.filter\((.*?)\)/;
var match = regex.exec(text);
firstPart = text.substring(match.index,match[1].length);
rest = text.substring(matchLength, text.length);
matches.push(firstPart);
regex = /\.filter\((.*?)\)/g;
while ((match = regex.exec(rest)) != null) {
matches.push(match[1]);
}
log(matches);
Looking for a better solution.
This will match the single example you posted:
<html>
<body>
<script type="text/javascript">
text = '#container a.filter(.top).filter(.bottom).filter(.middle)';
matches = text.match(/^[^.]*|\.[^.)]*(?=\))/g);
document.write(matches);
</script>
</body>
</html>
which produces:
#container a,.top,.bottom,.middle
EDIT
Here's a short explanation:
^ # match the beginning of the input
[^.]* # match any character other than '.' and repeat it zero or more times
#
| # OR
#
\. # match the character '.'
[^.)]* # match any character other than '.' and ')' and repeat it zero or more times
(?= # start positive look ahead
\) # match the character ')'
) # end positive look ahead
EDIT part II
The regex looks for two types of character sequences:
one ore more characters starting from the start of the string up to the first ., the regex: ^[^.]*
or it matches a character sequence starting with a . followed by zero or more characters other than . and ), \.[^.)]*, but must have a ) ahead of it: (?=\)). This last requirement causes .filter not to match.
You have to iterate, I think.
var head, filters = [];
text.replace(/^([^.]*)(\..*)$/, function(_, h, rem) {
head = h;
rem.replace(/\.filter\(([^)]*)\)/g, function(_, f) {
filters.push(f);
});
});
console.log("head: " + head + " filters: " + filters);
The ability to use functions as the second argument to String.replace is one of my favorite things about Javascript :-)
You need to do several matches repeatedly, starting where the last match ends (see while example at https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Global_Objects/RegExp/exec):
If your regular expression uses the "g" flag, you can use the exec method multiple times to find successive matches in the same string. When you do so, the search starts at the substring of str specified by the regular expression's lastIndex property. For example, assume you have this script:
var myRe = /ab*/g;
var str = "abbcdefabh";
var myArray;
while ((myArray = myRe.exec(str)) != null)
{
var msg = "Found " + myArray[0] + ". ";
msg += "Next match starts at " + myRe.lastIndex;
print(msg);
}
This script displays the following text:
Found abb. Next match starts at 3
Found ab. Next match starts at 9
However, this case would be better solved using a custom-built parser. Regular expressions are not an effective solution to this problem, if you ask me.
var text = '#container a.filter(.top).filter(.bottom).filter(.middle)';
var result = text.split('.filter');
console.log(result[0]);
console.log(result[1]);
console.log(result[2]);
console.log(result[3]);
text.split() with regex does the trick.
var text = '#container a.filter(.top).filter(.bottom).filter(.middle)';
var parts = text.split(/(\.[^.()]+)/);
var matches = [parts[0]];
for (var i = 3; i < parts.length; i += 4) {
matches.push(parts[i]);
}
console.log(matches);