I need to get part of a string inside round brackets, for example the string could be:
FirstName LastName ( myemail#address.org )
I'm using the following code:
let string = 'FirstName LastName ( myemail#address.org )';
const regExp = /(([^()]*))/g;
let email = string.match(regExp);
When I try to get and print the email variable I get this:
FirstName LastName ,,myemail#address.org,,
What's wrong with my code?
Thanks a lot for any help.
What's wrong with my code?
Your pattern is wrong and that is why you get the wrong result.
probably you wanted to match everything except parentheses in your pattern((([^()]*))) but this match all strings that are outside of parentheses too, so that's why you get FirstName LastName ,,myemail#address.org,, based on your pattern output is actually right. this is everything except parentheses.
You can use this pattern: (?<=\().*?(?=\))
Explanation:
(?<=\() This is called positive lookbehind and look back for checking (not matching just checking) pattern inside it is in the back or not? if it is then continue the matching.
.*? Match everything zero or more times.
(?=\)) This is called positive lookahead and look ahead for checking (not matching just checking) pattern inside it is in the front or not? if it is then continue the matching.
So overall this pattern searching for a string that first starts with ( and then matches everything till that next char is ).
See Regex Demo
Code:
let string = 'FirstName LastName ( myemail#address.org )';
const regExp = /(?<=\().*?(?=\))/g;
let email = string.match(regExp);
console.log(email[0].trim());
Related
I want to search in the array if theres the string that Im looking for, to do that im using match
const search_notes = array_notes.filter(notes => notes.real_content.toUpperCase().match(note.toUpperCase()));
as you can see, search_notes will give me an array with all the strings that at least has a character from the input or match completely, but theres a problem, because when I write , ), [], + or any regex symbol in the input it will gives me this error:
how can i solve this?
If you look at documentation for the match method (for instance, MDN's), you'll see that it accepts a RegExp object or a string, and if you give it a string, it passes that string into new RegExp. So naturally, characters that have special meaning in a regular expression need special treatment.
You don't need match, just includes, which doesn't do that:
const search_notes = array_notes.filter(
notes => notes.real_content.toUpperCase().includes(note.toUpperCase())
);
The error is simple. In JS I try to do somtehing to similar a preg_match in PHP. I found match function. I use this function to compare a value with strings elements. If found something return true, else return false.
I tried this
var sim_action = $(this);
if(sim_action.data("phone").toString().match("/^(+34|0034|34)+([67]){8})$/")){
But return this error.
Invalid regular expression: //^(+34|0034|34)+([67]){8})$//: Nothing
to repeat
So the question is. How can i add this string in JS match function?
You need to escape the + characters with a backslash: /^(\+34|0034|34)\+([67]){8})$/. You also have a closing bracket which doesn't have a matching opening bracket.
+ and () are metacharacters and if you want to refer to the literal, you need to escape them with a \. Here's a regex101 demo which highlights the errors with your regex
As for the regex, from wikipedia, I gather that spanish phone numbers have the format +34(6|7)xxxxxxxx
You can use this regex: /^(\+34|0034|34)[67]\d{8}$/
If you just want to check if the regex passes , you can use regex.test(<stringToBeTested>)
const regex = /^(\+34|0034|34)[67]\d{8}$/
const phone = "+34712345673";
if (regex.test(phone))
console.log("Valid phone number")
const phoneNumbers = ["+34712345673", "0034612345673", "+34812345673"]
phoneNumbers.forEach(p => console.log(regex.test(p)))
I am passing a URL to a block of code in which I need to insert a new element into the regex. Pretty sure the regex is valid and the code seems right but no matter what I can't seem to execute the match for regex!
//** Incoming url's
//** url e.g. api/223344
//** api/11aa/page/2017
//** Need to match to the following
//** dir/api/12ab/page/1999
//** Hence the need to add dir at the front
var url = req.url;
//** pass in: /^\/api\/([a-zA-Z0-9-_~ %]+)(?:\/page\/([a-zA-Z0-9-_~ %]+))?$/
var re = myregex.toString();
//** Insert dir into regex: /^dir\/api\/([a-zA-Z0-9-_~ %]+)(?:\/page\/([a-zA-Z0-9-_~ %]+))?$/
var regVar = re.substr(0, 2) + 'dir' + re.substr(2);
var matchedData = url.match(regVar);
matchedData === null ? console.log('NO') : console.log('Yay');
I hope I am just missing the obvious but can anyone see why I can't match and always returns NO?
Thanks
Let's break down your regex
^\/api\/ this matches the beginning of a string, and it looks to match exactly the string "/api"
([a-zA-Z0-9-_~ %]+) this is a capturing group: this one specifically will capture anything inside those brackets, with the + indicating to capture 1 or more, so for example, this section will match abAB25-_ %
(?:\/page\/([a-zA-Z0-9-_~ %]+)) this groups multiple tokens together as well, but does not create a capturing group like above (the ?: makes it non-captuing). You are first matching a string exactly like "/page/" followed by a group exactly like mentioned in the paragraph above (that matches a-z, A-Z, 0-9, etc.
?$ is at the end, and the ? means capture 0 or more of the precending group, and the $ matches the end of the string
This regex will match this string, for example: /api/abAB25-_ %/page/abAB25-_ %
You may be able to take advantage of capturing groups, however, and use something like this instead to get similar results: ^\/api\/([a-zA-Z0-9-_~ %]+)\/page\/\1?$. Here, we are using \1 to reference that first capturing group and match exactly the same tokens it is matching. EDIT: actually, this probably won't work, since the text after /api/ and the text after /page/ will most likely be different, carrying on...
Afterwards, you are are adding "dir" to the beginning of your search, so you can now match someting like this: dir/api/abAB25-_ %/page/abAB25-_ %
You have also now converted the regex to a string, so like Crayon Violent pointed out in their comment, this will break your expected funtionality. You can fix this by using .source on your regex: var matchedData = url.match(regVar.source); https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/source
Now you can properly match a string like this: dir/api/11aa/page/2017 see this example: https://repl.it/Mj8h
As mentioned by Crayon Violent in the comments, it seems you're passing a String rather than a regular expression in the .match() function. maybe try the following:
url.match(new RegExp(regVar, "i"));
to convert the string to a regular expression. The "i" is for ignore case; don't know that's what you want. Learn more here:
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp
I want to test if a sentence like type var1,var2,var3 is matching a text declaration or not.
So, I used the following code :
var text = "int a1,a2,a3",
reg = /int ((([a-z_A-Z]+[0-9]*),)+)$/g;
if (reg.test(text)) console.log(true);
else console.log(false)
The problem is that this regular expression returns false on text that is supposed to be true.
Could someone help me find a good regular expression matching expressions as in the example above?
You have a couple of mistekes.
As you wrote, the last coma is required at the end of the line.
I suppose you also want to match int abc123 as correct string, so you need to include letter to other characters
Avoid using capturing groups for just testing strings.
const str = 'int a1,a2,a3';
const regex = /int (?:[a-zA-Z_](?:[a-zA-Z0-9_])*(?:\,|$))+/g
console.log(regex.test(str));
You will need to add ? after the comma ,.
This token ? matches between zero and one.
Notice that the last number in your text a3 does not have , afterward.
int ((([a-z_A-Z]+[0-9]*),?)+)$
I am trying to match everything after (but not including!) the last occurrence of a string in JavaScript.
The search, for example, is:
[quote="user1"]this is the first quote[/quote]\n[quote="user2"]this is the 2nd quote and some url https://www.google.com/[/quote]\nThis is all the text I\'m wirting about myself.\n\nLook at me ma. Javascript.
Edit: I'm looking to match everything after the last quote block. So I was trying to match everything after the last occurrence of "quote]" ? Idk if this is the best solution but its what i've been trying.
I'll be honest, i suck at this Regex stuff.. here is what i've been trying with the results..
regex = /(quote\].+)(.*)/ig; // Returns null
regex = /.+((quote\]).+)$/ig // Returns null
regex = /( .* (quote\]) .*)$/ig // Returns null
I have made a JSfiddle for anyone to have a play with here:
https://jsfiddle.net/au4bpk0e/
One option would be to match everything up until the last [/quote], and then get anything following it. (example)
/.*\[\/quote\](.*)$/i
This works since .* is inherently greedy, and it will match every up until the last \[\/quote\].
Based on the string you provided, this would be the first capturing group match:
\nThis is all the text I\'m wirting about myself.\n\nLook at me ma. Javascript.
But since your string contains new lines, and . doesn't match newlines, you could use [\s\S] in place of . in order to match anything.
Updated Example
/[\s\S]*\[\/quote\]([\s\S]*)$/i
You could also avoid regex and use the .lastIndexOf() method along with .slice():
Updated Example
var match = '[\/quote]';
var textAfterLastQuote = str.slice(str.lastIndexOf(match) + match.length);
document.getElementById('res').innerHTML = "Results: " + textAfterLastQuote;
Alternatively, you could also use .split() and then get the last value in the array:
Updated Example
var textAfterLastQuote = str.split('[\/quote]').pop();
document.getElementById('res').innerHTML = "Results: " + textAfterLastQuote;