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How to remove text from a string?

I've got a data-123 string.

How can I remove data- from the string while leaving the 123?


C
Community

var ret = "data-123".replace('data-',''); console.log(ret); //prints: 123

Docs.

For all occurrences to be discarded use:

var ret = "data-123".replace(/data-/g,'');

PS: The replace function returns a new string and leaves the original string unchanged, so use the function return value after the replace() call.


How to replace multiple expressions? Do you have to use multiple .replace calls?
For all occurrences to be discarded you can use replaceAll
M
Meetai.com

This doesn't have anything to do with jQuery. You can use the JavaScript replace function for this:

var str = "data-123";
str = str.replace("data-", "");

You can also pass a regex to this function. In the following example, it would replace everything except numerics:

str = str.replace(/[^0-9\.]+/g, "");

Could you explain what the regex does? I dont get it why it replaces string except numbers if 0-9 was indicated.
@rotimi-best [^0-9\.] means it will catch any letter that is not a digit or a period. notice the caret right after the first square bracket.
l
laaposto

You can use "data-123".replace('data-','');, as mentioned, but as replace() only replaces the FIRST instance of the matching text, if your string was something like "data-123data-" then

"data-123data-".replace('data-','');

will only replace the first matching text. And your output will be "123data-"

DEMO

So if you want all matches of text to be replaced in string you have to use a regular expression with the g flag like that:

"data-123data-".replace(/data-/g,'');

And your output will be "123"

DEMO2


M
Mr. J

You can use slice(), if you will know in advance how many characters need slicing off the original string. It returns characters between a given start point to an end point.

string.slice(start, end);

Here are some examples showing how it works:

var mystr = ("data-123").slice(5); // This just defines a start point so the output is "123"
var mystr = ("data-123").slice(5,7); // This defines a start and an end  so the output is "12"

Demo


I want to remove string starting from character position to the end.
J
James Hill

Plain old JavaScript will suffice - jQuery is not necessary for such a simple task:

var myString = "data-123";
var myNewString = myString.replace("data-", "");

See: .replace() docs on MDN for additional information and usage.


A
Ajitej Kaushik

Ex:-

var value="Data-123";
var removeData=value.replace("Data-","");
alert(removeData);

Hopefully this will work for you.


T
Tsafack Dagha cedrick

1- If is the sequences into your string:

let myString = "mytest-text";
let myNewString = myString.replace("mytest-", "");

the answer is text

2- if you whant to remove the first 3 characters:

"mytest-text".substring(3);

the answer is est-text


H
HoldOffHunger

This little function I made has always worked for me :)

String.prototype.deleteWord = function (searchTerm) {
    var str = this;
    var n = str.search(searchTerm);
    while (str.search(searchTerm) > -1) {
        n = str.search(searchTerm);
        str = str.substring(0, n) + str.substring(n + searchTerm.length, str.length);
    }
    return str;
}

// Use it like this:
var string = "text is the cool!!";
string.deleteWord('the'); // Returns text is cool!!

I know it is not the best, but It has always worked for me :)


You are showing in your answer how replace function of string works more or less, but indeed just using the replace function of string is much more simpler and easier code then yours!
New to JavaScript but this was the only solution that worked for me. I disagree with the above comment because this is a while loop and not the same as a simple replace.
佚名

I was used to the C# (Sharp) String.Remove method. In Javascript, there is no remove function for string, but there is substr function. You can use the substr function once or twice to remove characters from string. You can make the following function to remove characters at start index to the end of string, just like the c# method first overload String.Remove(int startIndex):

function Remove(str, startIndex) {
    return str.substr(0, startIndex);
}

and/or you also can make the following function to remove characters at start index and count, just like the c# method second overload String.Remove(int startIndex, int count):

function Remove(str, startIndex, count) {
    return str.substr(0, startIndex) + str.substr(startIndex + count);
}

and then you can use these two functions or one of them for your needs!

Example:

alert(Remove("data-123", 0, 5));

Output: 123


A
ARC
str.split('Yes').join('No'); 

This will replace all the occurrences of that specific string from original string.


B
Brett DeWoody

Using match() and Number() to return a number variable:

Number(("data-123").match(/\d+$/));

// strNum = 123

Here's what the statement above does...working middle-out:

str.match(/\d+$/) - returns an array containing matches to any length of numbers at the end of str. In this case it returns an array containing a single string item ['123']. Number() - converts it to a number type. Because the array returned from .match() contains a single element Number() will return the number.


K
Kamil Kiełczewski

Performance

Today 2021.01.14 I perform tests on MacOs HighSierra 10.13.6 on Chrome v87, Safari v13.1.2 and Firefox v84 for chosen solutions.

Results

For all browsers

solutions Ba, Cb, and Db are fast/fastest for long strings

solutions Ca, Da are fast/fastest for short strings

solutions Ab and E are slow for long strings

solutions Ba, Bb and F are slow for short strings

https://i.stack.imgur.com/jwLqa.png

Details

I perform 2 tests cases:

short string - 10 chars - you can run it HERE

long string - 1 000 000 chars - you can run it HERE

Below snippet presents solutions Aa Ab Ba Bb Ca Cb Da Db E F

// https://stackoverflow.com/questions/10398931/how-to-strToRemove-text-from-a-string // https://stackoverflow.com/a/10398941/860099 function Aa(str,strToRemove) { return str.replace(strToRemove,''); } // https://stackoverflow.com/a/63362111/860099 function Ab(str,strToRemove) { return str.replaceAll(strToRemove,''); } // https://stackoverflow.com/a/23539019/860099 function Ba(str,strToRemove) { let re = strToRemove.replace(/[.*+?^${}()|[\]\\]/g, '\\$&'); // regexp escape char return str.replace(new RegExp(re),''); } // https://stackoverflow.com/a/63362111/860099 function Bb(str,strToRemove) { let re = strToRemove.replace(/[.*+?^${}()|[\]\\]/g, '\\$&'); // regexp escape char return str.replaceAll(new RegExp(re,'g'),''); } // https://stackoverflow.com/a/27098801/860099 function Ca(str,strToRemove) { let start = str.indexOf(strToRemove); return str.slice(0,start) + str.slice(start+strToRemove.length, str.length); } // https://stackoverflow.com/a/27098801/860099 function Cb(str,strToRemove) { let start = str.search(strToRemove); return str.slice(0,start) + str.slice(start+strToRemove.length, str.length); } // https://stackoverflow.com/a/23181792/860099 function Da(str,strToRemove) { let start = str.indexOf(strToRemove); return str.substr(0, start) + str.substr(start + strToRemove.length); } // https://stackoverflow.com/a/23181792/860099 function Db(str,strToRemove) { let start = str.search(strToRemove); return str.substr(0, start) + str.substr(start + strToRemove.length); } // https://stackoverflow.com/a/49857431/860099 function E(str,strToRemove) { return str.split(strToRemove).join(''); } // https://stackoverflow.com/a/45406624/860099 function F(str,strToRemove) { var n = str.search(strToRemove); while (str.search(strToRemove) > -1) { n = str.search(strToRemove); str = str.substring(0, n) + str.substring(n + strToRemove.length, str.length); } return str; } let str = "data-123"; let strToRemove = "data-"; [Aa,Ab,Ba,Bb,Ca,Cb,Da,Db,E,F].map( f=> console.log(`${f.name.padEnd(2,' ')} ${f(str,strToRemove)}`)); This shippet only presents functions used in performance tests - it not perform tests itself!

And here are example results for chrome

https://i.stack.imgur.com/kb3hi.png


z
zcoop98

Another way to replace all instances of a string is to use the new (as of August 2020) String.prototype.replaceAll() method.

It accepts either a string or RegEx as its first argument, and replaces all matches found with its second parameter, either a string or a function to generate the string.

As far as support goes, at time of writing, this method has adoption in current versions of all major desktop browsers* (even Opera!), except IE. For mobile, iOS SafariiOS 13.7+, Android Chromev85+, and Android Firefoxv79+ are all supported as well.

* This includes Edge/ Chrome v85+, Firefox v77+, Safari 13.1+, and Opera v71+

It'll take time for users to update to supported browser versions, but now that there's wide browser support, time is the only obstacle.

References:

MDN

Can I Use - Current Browser Support Information

TC39 Proposal Repo for .replaceAll()

You can test your current browser in the snippet below:

//Example coutesy of MDN: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/replaceAll const p = 'The quick brown fox jumps over the lazy dog. If the dog reacted, was it really lazy?'; const regex = /dog/gi; try { console.log(p.replaceAll(regex, 'ferret')); // expected output: "The quick brown fox jumps over the lazy ferret. If the ferret reacted, was it really lazy?" console.log(p.replaceAll('dog', 'monkey')); // expected output: "The quick brown fox jumps over the lazy monkey. If the monkey reacted, was it really lazy?" console.log('Your browser is supported!'); } catch (e) { console.log('Your browser is unsupported! :('); } .as-console-wrapper: { max-height: 100% !important; }


W
Willie

Make sure that if you are replacing strings in a loop that you initiate a new Regex in each iteration. As of 9/21/21, this is still a known issue with Regex essentially missing every other match. This threw me for a loop when I encountered this the first time:

yourArray.forEach((string) => {
    string.replace(new RegExp(__your_regex__), '___desired_replacement_value___');
})

If you try and do it like so, don't be surprised if only every other one works

let reg = new RegExp('your regex');
yourArray.forEach((string) => {
    string.replace(reg, '___desired_replacement_value___');
})

S
S. Hesam
const newString = string.split("data-").pop();
console.log(newString);