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())
);
Related
Let's assume I have an string... I want to convert them to numbers.. and It will only work for alphabets...
if my string contains comma or dot... I would like to avoid it...
I'm working with words by word. so if the string is--
"Hi, let's play!"
it should be converted to--
"4510, 584578'52 69775246!"
how can I do it?
function hasNumber(gottenWord) {
return (/\d/.test(gottenWord));
}
const numberTrue = hasNumber(gottenWord);
I was able to search for numbers but not sure how to search for symbols.. and I even have some custom symbols to search.
If all you want is to avoid anything that's not in abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ then the easiest way is to change \d to [^a-zA-Z]. [] indicates a character set, and starting a set with ^ means "not these".
I have a following string:
Text
I want to extract from this string, with the use of JavaScript 'pl' or 'pl_company_com'
There are a few variables:
jan_kowalski is a name and surname it can change, and sometimes even have 3 elements
the country code (in this example 'pl') will change to other en / de / fr (this is that part of the string i want to get)
the rest of the string remains the same for every case (beginning + everything after starting with _company_com ...
Ps. I tried to do it with split, but my knowledge of JS is very basic and I cant get what i want, plase help
An alternative to Randy Casburn's solution using regex
let out = new URL('https://my.domain.com/personal/jan_kowalski_pl_company_com/Documents/Forms/All.aspx').href.match('.*_(.*_company_com)')[1];
console.log(out);
Or if you want to just get that string with those country codes you specified
let out = new URL('https://my.domain.com/personal/jan_kowalski_pl_company_com/Documents/Forms/All.aspx').href.match('.*_((en|de|fr|pl)_company_com)')[1];
console.log(out);
let out = new URL('https://my.domain.com/personal/jan_kowalski_pl_company_com/Documents/Forms/All.aspx').href.match('.*_((en|de|fr|pl)_company_com)')[1];
console.log(out);
A proof of concept that this solution also works for other combinations
let urls = [
new URL('https://my.domain.com/personal/jan_kowalski_pl_company_com/Documents/Forms/All.aspx'),
new URL('https://my.domain.com/personal/firstname_middlename_lastname_pl_company_com/Documents/Forms/All.aspx')
]
urls.forEach(url => console.log(url.href.match('.*_(en|de|fr|pl).*')[1]))
I have been very successful before with this kind of problems with regular expressions:
var string = 'Text';
var regExp = /([\w]{2})_company_com/;
find = string.match(regExp);
console.log(find); // array with found matches
console.log(find[1]); // first group of regexp = country code
First you got your given string. Second you have a regular expression, which is marked with two slashes at the beginning and at the end. A regular expression is mostly used for string searches (you can even replace complicated text in all major editors with it, which can be VERY useful).
In this case here it matches exactly two word characters [\w]{2} followed directly by _company_com (\w indicates a word character, the [] group all wanted character types, here only word characters, and the {}indicate the number of characters to be found). Now to find the wanted part string.match(regExp) has to be called to get all captured findings. It returns an array with the whole captured string followed by all capture groups within the regExp (which are denoted by ()). So in this case you get the country code with find[1], which is the first and only capture group of the regular expression.
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?$. Here, we are using \1 to reference that first capturing group and match exactly the same tokens it is matching. EDIT: actually, this probably won't work, since the text after /api/ and the text after /page/ will most likely be different, carrying on...
Afterwards, you are are adding "dir" to the beginning of your search, so you can now match someting like this: dir/api/abAB25-_ %/page/abAB25-_ %
You have also now converted the regex to a string, so like Crayon Violent pointed out in their comment, this will break your expected funtionality. You can fix this by using .source on your regex: var matchedData = url.match(regVar.source); https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/source
Now you can properly match a string like this: dir/api/11aa/page/2017 see this example: https://repl.it/Mj8h
As mentioned by Crayon Violent in the comments, it seems you're passing a String rather than a regular expression in the .match() function. maybe try the following:
url.match(new RegExp(regVar, "i"));
to convert the string to a regular expression. The "i" is for ignore case; don't know that's what you want. Learn more here:
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp
I am trying to extract the first character after the last underscore in a string with an unknown number of '_' in the string but in my case there will always be one, because I added it in another step of the process.
What I tried is this. I also tried the regex by itself to extract from the name, but my result was empty.
var s = "XXXX-XXXX_XX_DigitalF.pdf"
var string = match(/[^_]*$/)[1]
string.charAt(0)
So the final desired result is 'D'. If the RegEx can only get me what is behind the last '_' that is fine because I know I can use the charAt like currently shown. However, if the regex can do the whole thing, even better.
If you know there will always be at least one underscore you can do this:
var s = "XXXX-XXXX_XX_DigitalF.pdf"
var firstCharAfterUnderscore = s.charAt(s.lastIndexOf("_") + 1);
// OR, with regex
var firstCharAfterUnderscore = s.match(/_([^_])[^_]*$/)[1]
With the regex, you can extract just the one letter by using parentheses to capture that part of the match. But I think the .lastIndexOf() version is easier to read.
Either way if there's a possibility of no underscores in the input you'd need to add some additional logic.
I'm trying to get the numbers/stings out of a string that looks like this
"[123][456][abc]"
Also I don't want to include "[" or "]" and I want to keep the values separate.
Try this on for size.
/\[(\d+|[a-zA-Z]+)\]/
Edit:
If you can support lookahead and lookbehind
/(?<=\[)(\d+|[a-zA-Z]+)(?=\])/
Another edit:
try this in javascript
var text = "[12][34][56][bxe]";
var array = text.match(/(\d+|[a-zA-Z]+)/g);
This would be a lot easier if we knew the language. For example, in Javascript you can do:
"[123][456][abc]".split(/[\[\]]/);
and similarly in Python:
>>> import re
>>> re.split(r'[\[\]]', "[123][456][abc]")
['', '123', '', '456', '', 'abc', '']
I'm sure there are ways to do this in other languages, too.
See http://www.regular-expressions.info/javascript.html, particularly the "How to Use The JavaScript RegExp Object" section:
If you want to retrieve the part of
the string that was matched, call the
exec() function of the RegExp object
that you created, e.g.: mymatch =
myregexp.exec("subject"). This
function returns an array. The zeroth
item in the array will hold the text
that was matched by the regular
expression. The following items
contain the text matched by the
capturing parentheses in the regexp,
if any. mymatch.length indicates the
length of the match[] array, which is
one more than the number of capturing
groups in your regular expression.
mymatch.index indicates the character
position in the subject string at
which the regular expression matched.
mymatch.input keeps a copy of the
subject string.
That explains how to access individual parenthesized groups. You can use that in conjunction with a pattern like /\[(\w+)\]/g