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How to remove + from string except at beginning using regex [duplicate]

This question already has answers here:
Replace all occurrences of character except in the beginning of string (Regex)
(3 answers)
Remove all occurrences of a character except the first one in string with javascript
(1 answer)
Closed 1 year ago.
I’m looking to remove + from a string except at the initial position using javascript replace and regex.
Input: +123+45+
Expected result: +12345
Please help

const string = '+123+45+'
console.log(string.replace(/([^^])\+/g, '$1'))
https://regexr.com/61g3c

You can try the below regex java script. Replace all plus sign except first occurrence.
const givenString = '+123+45+'
let index = 0
let result = givenString.replace(/\+/g, (item) => (!index++ ? item : ""));
console.log(result)

input = '+123+45+';
regex = new RegExp('(?!^)(\\+)', 'g');
output = input.replace(regex, '');
console.log(output);

How to check if string has vowels? [duplicate]

This question already has answers here:
Counting the vowels in a string using Regular Expression
(2 answers)
Closed 1 year ago.
I tried to write a function which checks if a given string contains vowels and I cannot see why it works for some words 'cat' and 'why' but not 'DOG', i believe that i have accounted for uppercase.
const containsVowels = string => {
var lowerCase = string.toLowerCase();
var word = lowerCase.split("");
var vowelsArray = ["a","o","i","u","y"];
const result = word.filter(letter => vowelsArray.includes(letter));
return result.includes("a","o","i","u","y");
};

includes takes only 2 parameters, the first one being searchElement and second parameter being fromIndex.
Reference : https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/includes#parameters
You wouldn't want to do the last check if the result array contains vowels or not, because in the previous step itself you are filtering out the word to get array that contains only vowels. So just check if the array is empty or it contains any elements inside it.
const containsVowels = str => {
let lowerCase = str.toLowerCase();
let word = lowerCase.split("");
let vowelsArray = ["a","o","i","u","y"];
const result = word.filter(letter => vowelsArray.includes(letter));
return result.length > 0;
};
console.log(containsVowels("cat"));
console.log(containsVowels("DOG"));
console.log(containsVowels("BCDF"));
Suggestion: Don't use built in keywords as variables.
As pointed out by Muhammad, we can regex to find if the string contains vowels
const containsVowel = str => {
const vowelRegex = /[aeiou]/i;
return vowelRegex.test(str);
};

2 Problems,
Why would you use includes twice ?
&
You cannot use includes like
result.includes("a","o","i","u","y");
includes only accepts 2 param:
includes(searchElement, fromIndex)
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/includes
By filtering, you already know the result.
What you should do is, compare the length of the result:
const containsVowels = string => {
let lowerCase = string.toLowerCase();
let word = lowerCase.split("");
let vowelsArray = ["a","o","i","u","y"];
const result = word.filter(letter => vowelsArray.includes(letter));
return result.length > 0 ? true : false
};

use regex to get the result.
var regEx = /[aeiou]/gi
var test_string = "Cat";
var match = test_string.match(regEx)
if(match)
console.log("Match found", match)

when you write something like this
result.includes("a","o","i","u","y")
this compare with only it's first element which is "a" and one thing you don't need to write the above mentioned code further.
After filtering just replace the above code with
return result.length > 0 ? true : false

Finding ALL positions of a string within another string [duplicate]

This question already has answers here:
How can I match overlapping strings with regex?
(6 answers)
JS Match all occurrences of substring in a string
(2 answers)
Closed 3 years ago.
I can't find out a solution to the following problem and it's driving me nuts. I need to find every position of a string within another string.
This is what I have come up with:
function getMatchIndices(regex, str) {
let result = [];
let match;
let regex = new RegExp(regex, 'g');
while (match = regex.exec(str))
result.push(match.index);
return result;
}
const line = "aabaabbaababaababaaabaabaaabaabbabaababa";
const rule = 'aba';
const indices = getMatchIndices(new RegExp(rule, "g"), line);
console.log(indices);
Now, the issue is that this does NOT match aba's that are formed in the middle of two other matches...
Here is an image illustrating the problem:
Any ideas?

I realize this is NOT a Regex solution. So it might not be what you need.
Hope it helps.
function getMatchIndices(r, str) {
const indices = [];
str.split('').forEach((v,i) => {
if(r === str.substring(i,i+r.length)) {
indices.push(i);
}
});
return indices;
}
const line = "aabaabbaababaababaaabaabaaabaabbabaababa";
const rule = 'aba';
const indices = getMatchIndices(rule, line);
console.log(indices);

How can i get all clean links via Regex without pattern string [duplicate]

This question already has answers here:
How do you access the matched groups in a JavaScript regular expression?
(23 answers)
Closed 4 years ago.
when i trying this match im getting links like this;
Result:
"video","src":"https:\/\/video-mxp1-1.xx.fbcdn.net\/v\/t42.9040-2\/34384597_178997956146914_227512178675023872_n.mp4"
I want get just cleaned link like this:https:\/\/video-mxp1-1.xx.fbcdn.net\/v\/t42.9040-2\/34384597_178997956146914_227512178675023872_n.mp4
Thanks for your helps;
My codes are below:
var VideoLinks='"type":"video","src":"https:\\\/\\\/video-mxp1-1.xx.fbcdn.net\\\/v\\\/t42.9040-2\\\/34333324_n.mp4?_nc_cat=0&efg=ey1&oe=5B211DB0","width":null"type":"video","src":"https:\\\/\\\/video-mxp1-1.xx.fbcdn.net\\\/v\\\/t42.9040-2\\\/34333324_n.mp4?_nc_cat=0&efg=ey1&oe=5B211DB0","width":null';
My Pattern
pattern =/"video","src":"(.*?)"/g;
var videos=Sitestring.match(pattern);
console.log(videos);

const str = '"video","src":"https:\vid1.mp4"';
const regex = new RegExp('src\":\"(.*)\"', 'i');
console.log(regex.exec(str)[1]);
And about multiple occurences
function getMatch(str, regex) {
const matches = [];
let oneMatch;
do {
oneMatch = regex.exec(str);
if (!oneMatch) {
return matches;
}
matches.push(oneMatch[1]);
} while (oneMatch);
}
const str = '"video","src":"https:vid1.mp4","video","src":"https:vid2.mp4","video","src":"https:vid3.mp4"';
const regex = new RegExp('src\":\"(.*?)\"', 'ig');
console.log(getMatch(str, regex));

Is there a way to replace a string in a text without spaces? [duplicate]

This question already has answers here:
Replace method doesn't work
(4 answers)
Closed 6 years ago.
Is there a way to replace something like this:
testHoraciotestHellotest
And replace the 'test' word via javascript, I've tried with the .replace() function but it didn't work

str.replace() also accepts regular expressions, so you can use /test/g to match all instances of 'test' in the string.
var str = "testHoraciotestHellotest";
var res = str.replace(/test/g, "replaced");
console.log(res);

use g to make a global replace to the string
var str = "testHoraciotestHellotest";
var res = str.replace(/test/g, "word");
console.log(res);

It's simple.
var str = "testHoraciotestHellotest";
var res = str.replace("test", "test1");
console.log(res);
If you want to replace all occurances of 'test' rather than just one, use the following trick instead:
var res = str.split("test").join ("test1");