Replace all spaces in a string with '+'

Question

I have a string that contains multiple spaces. I want to replace these with a plus symbol. I thought I could use

var str = 'a b c';
var replaced = str.replace(' ', '+');

but it only replaces the first occurrence. How can I get it replace all occurrences?

Are you trying to do URL-encoding of a string? If so, it's better to ask for help with that than just how to handle the spaces. — Lasse V. Karlsen, Sep 25 '10 at 18:16
@Lasse, I suppose ultimately that is what I'm trying to do as the string that I want to format will eventually become part of a URL. However, I think the question still stands on its own merrit, as replacing all occurrences of a sub-string inside a string isn't immediately obvious. — DaveDev, Sep 25 '10 at 20:13
Right, that was my suspicion too. The answer to that one is: use `encodeURIComponent()`. Don't try to hack it yourself with string replace; it's a lot trickier than you think. This will encode spaces to `%20` rather than `+` though. `%20` is just as valid (in fact more valid, as it works in path components, whereas `+` only means a space in query components), but if you want it to look marginally prettier you can always do a `replace(/%20/g, '+')` afterwards of course. You might be tempted to use `escape()` because it does use `+`, but it also gets all non-ASCII characters wrong—avoid. — bobince, Sep 26 '10 at 00:39
I'll agree with that, the question has merit on its own :) I just wanted to know if that's where you were trying to end up, there might be better solutions for you. But yes, the question is good on its own, no doubt about that. I know enough javascript to scrape by, and that .replace didn't replace all the occurances was news to me. — Lasse V. Karlsen, Sep 26 '10 at 06:55
Comparison of regex and split/join on tiny and longer strings. http://jsperf.com/replace-characters-in-string — iabw, Jul 20 '12 at 18:48
The answer of @Andrew below is the most right one, `str.replace(/\s+/g, '+')` because in case your string contrains chaining whitespaces, it will also replace chaning whiteplaces with one replacement, e.g. `a----b--c-d` will be `a+b+c+d`. It makes more sense. Isn't it? — O Connor, Jan 21 '20 at 16:04
In the latest versions of most popular browsers, you can use replaceAll as shown here: `let result = "a b c".replaceAll(" ", "+");` `// result is "a+b+c"` — Sunny Sultan, Jan 17 '21 at 10:20

score 612 · Answer 1 · answered Sep 25 '10 at 18:13

612

You need the /g (global) option, like this:

var replaced = str.replace(/ /g, '+');

You can give it a try here. Unlike most other languages, JavaScript, by default, only replaces the first occurrence.

answered Sep 25 '10 at 18:13

Nick Craver

623,446
136
1,297
1,155

1

this has better readability than the split/join version imho – bobmoff Dec 13 '19 at 15:31
1

Oh, my ... I tried countless times of '/ /g' or something like that, there should be no quotation mark. Astonished me. – Zhang Jun 18 '21 at 13:28

Dagg Nabbit · Accepted Answer · 2014-04-29T21:06:16.583

599

Here's an alternative that doesn't require regex:

var str = 'a b c';
var replaced = str.split(' ').join('+');

edited Apr 29 '14 at 21:06

answered Sep 25 '10 at 19:05

Dagg Nabbit

75,346
19
113
141

31

This selected solution is slower on large replacement compared to the reg expression version. Test with the 3 solutions posted: http://jsbin.com/isadi3/2 Firefox has minimal timing difference, IE has a noticeable difference. So if speed matters and you have a large set of replacements, reg exp is the way to go. – epascarello Sep 30 '10 at 04:27
51

use str = str.replace(/\s/g, "+"); – Jitendra Pancholi Jul 16 '14 at 09:46
4

@JitendraPancholi that replaces all whitespace, not just the space character. The other regex answer here is fine. – Dagg Nabbit Jul 16 '14 at 10:23
@DaggNabbit: As per the question, he wants to replace white spaces with + symbol, even your solution is doing the same. – Jitendra Pancholi Jul 16 '14 at 10:45
2

@JitendraPancholi he wants to replace *spaces*, not "white spaces." In this context I assume by *spaces* he means only the space character, not just any old whitespace like `/s` would match. Particularly because he is doing this in JavaScript, and replacing the space character (but not other whitespace) with the `+` character is a standard way to encode URLs. This is probably why the regex solution that only replaces space characters has 10x the votes of the one that replaces all whitespace. – Dagg Nabbit Jul 16 '14 at 10:52
Using a split and join is an overhead if we have large data. So its always good to opt a regular expression for the same if possible. http://jsfiddle.net/aC5ZW/ – Jitendra Pancholi Jul 16 '14 at 10:56
http://jsfiddle.net/aC5ZW/3/ having a tab, line feed or form feed in the string, my solution works for all. – Jitendra Pancholi Jul 16 '14 at 10:59
re: overhead: see the last comment on the question. It's significantly less overhead in some browsers for a small amount of data, which is probably what he's dealing with. In some browsers, it's more. Performance is a moot point here, one goes faster and the other goes slower as browsers make tweaks between versions – Dagg Nabbit Jul 16 '14 at 11:01
re: tabs: you're missing my point. If he's doing what it looks like he's doing, he's not going to *want* it to convert all those characters to `+`. He's only going to want to convert the space character. – Dagg Nabbit Jul 16 '14 at 11:02
I got your point and also had a look to the comparison, and if we have even 30 replacement, spit/join was apx 90% slower than regex, with 2 replacements, it was only 23% slower. – Jitendra Pancholi Jul 16 '14 at 11:05
It's most likely a URL. You're not going to have 30 spaces in a URL. – Dagg Nabbit Jul 16 '14 at 11:06
And instead of \s, If i change it to ' ', my solution would still better. – Jitendra Pancholi Jul 16 '14 at 11:06
Yes, a regex solution with a literal space character would probably be better. This answer was meant as an alternative for people who didn't want to use regex. That's why it begins with "Here's an alternative." I can't help that the OP accepted it. – Dagg Nabbit Jul 16 '14 at 11:07
Yes, it is mentioned in comments below the question, url may have that replacements, Even i worked on a project which had the same requirement. I had around 30+ replacement in the url. – Jitendra Pancholi Jul 16 '14 at 11:08
1

If your projects are using URLs with 30 spaces in them, you have bigger things to worry about than microptimizing string replacements. – Dagg Nabbit Jul 16 '14 at 11:09
@DaggNabbit: See the last comment in my solution. :D – Jitendra Pancholi May 15 '15 at 11:15
Split() and Join() are way overpowered and unnecessary here, when a regex is infinitely more efficient. – HoldOffHunger Sep 19 '17 at 19:33
I use a version inspired by the trim polyfill str = str.replace(/[\s\uFEFF\xA0]/g, "+"); ... IE "yeeay" – stefan Mar 23 '18 at 11:32
https://stackoverflow.com/a/3794936/4429637 this is the best solution. – Lasitha Lakmal Aug 03 '19 at 21:15

score 130 · Answer 3 · answered Sep 25 '10 at 19:01

130

var str = 'a b c';
var replaced = str.replace(/\s/g, '+');

answered Sep 25 '10 at 19:01

epascarello

204,599
20
195
236

9

Cleaner and faster than the chosen solution; works where `/ /g` does not. – Autumn Leonard Dec 15 '15 at 17:35

score 104 · Answer 4 · edited Jul 31 '20 at 17:28

104

You can also do it like:

str = str.replace(/\s/g, "+");

Have a look at this fiddle.

edited Jul 31 '20 at 17:28

HoldOffHunger

18,769
10
104
133

answered Jul 16 '14 at 09:45

Jitendra Pancholi

7,897
12
51
84

Could you please add explanation to why this is good solution to the problem. – Matas Vaitkevicius Jul 16 '14 at 10:47
1

Wasn't my downvote, I got a review task to check due to length of content. I assume someone more demanding didn't see explanation and downvoted without bothering to comment. Please put your comment into answer. – Matas Vaitkevicius Jul 16 '14 at 10:53
Ok, i have added fiddle in my answer. – Jitendra Pancholi Jul 16 '14 at 10:55
13

Another possible reason for downvote is that this answer was [already posted](http://stackoverflow.com/a/3795130/451518) almost four years ago – default locale Jul 25 '14 at 13:25
2

@Jitendra Pancholi Thank you very much, you answer did help me, cuz I had some Japanese :) spaces, that I won't be able to replace by .split(' ').join('+'); Your answer did help me. Thanks man. – whitesiroi May 15 '15 at 10:48

score 34 · Answer 5 · answered Oct 12 '12 at 04:36

34

Use global search in the string. g flag

str.replace(/\s+/g, '+');

source: replaceAll function

answered Oct 12 '12 at 04:36

Andrew

483
5
3

1

I have tested many regex above your answer, but your answer is the most right, because it also replaces multiple chainning white spaces. – O Connor Jan 21 '20 at 15:57
4

Does not work: [Demo](https://jsbin.com/kocufiteva/edit?html,js,console,output) Input: `"hello !!!"`, expected output: `"hello++++!!!"`, actual output: `"hello+!!!"` – HoldOffHunger Jul 31 '20 at 17:41

Mark Byers · Answer 6 · 2010-09-25T18:23:49.010

32

Use a regular expression with the g modifier:

var replaced = str.replace(/ /g, '+');

From Using Regular Expressions with JavaScript and ActionScript:

/g enables "global" matching. When using the replace() method, specify this modifier to replace all matches, rather than only the first one.

edited Sep 25 '10 at 18:23

answered Sep 25 '10 at 18:13

Mark Byers

811,555
193
1,581
1,452

score 16 · Answer 7 · edited Jan 15 '14 at 13:31

16

You need to look for some replaceAll option

str = str.replace(/ /g, "+");

this is a regular expression way of doing a replaceAll.

function ReplaceAll(Source, stringToFind, stringToReplace) {
    var temp = Source;
    var index = temp.indexOf(stringToFind);

    while (index != -1) {
        temp = temp.replace(stringToFind, stringToReplace);
        index = temp.indexOf(stringToFind);
    }

    return temp;
}

String.prototype.ReplaceAll = function (stringToFind, stringToReplace) {
    var temp = this;
    var index = temp.indexOf(stringToFind);

    while (index != -1) {
        temp = temp.replace(stringToFind, stringToReplace);
        index = temp.indexOf(stringToFind);
    }

    return temp;

};

edited Jan 15 '14 at 13:31

mustafa.0x

1,476
2
17
30

answered Sep 25 '10 at 18:14

sushil bharwani

29,685
30
94
128

4

Wow. Er... there's a *much* simpler idiom for this: `str.split(stringToFind).join(stringToReplace)`. – bobince Sep 25 '10 at 18:30
1

Wow is that inefficient. – epascarello Sep 25 '10 at 19:02
@epascarello actually that performs way faster than a regex or above indfedelity :) – Caspar Kleijne Sep 25 '10 at 19:16
3

@Casper What browser are you seeing that in? http://jsbin.com/isadi3/edit Looking at the code it looks slow. Just for kicks I coded up a quick test and it is like 100X slower in browsers I tested it in. – epascarello Sep 26 '10 at 03:27

score 7 · Answer 8 · edited Jun 20 '20 at 09:12

7

NON BREAKING SPACE ISSUE

In some browsers

(MSIE "as usually" ;-))

replacing space in string ignores the non-breaking space (the 160 char code).

One should always replace like this:

myString.replace(/[ \u00A0]/, myReplaceString)

Very nice detailed explanation:

http://www.adamkoch.com/2009/07/25/white-space-and-character-160/

edited Jun 20 '20 at 09:12

Community

1
1

answered Jul 07 '14 at 09:10

Motlicek Petr

767
9
10

score -3 · Answer 9 · edited Jul 09 '12 at 01:56

-3

Do this recursively:

public String replaceSpace(String s){
    if (s.length() < 2) {
        if(s.equals(" "))
            return "+";
        else
            return s;
    }
    if (s.charAt(0) == ' ')
        return "+" + replaceSpace(s.substring(1));
    else
        return s.substring(0, 1) + replaceSpace(s.substring(1));
}

edited Jul 09 '12 at 01:56

Kijewski

25,517
12
101
143

answered Jul 06 '12 at 17:56

Rick

3
1

4

There are already better solutions provided in the answers here. – Rodney P. Barbati Dec 05 '17 at 17:53

Replace all spaces in a string with '+'

9 Answers9

NON BREAKING SPACE ISSUE

Linked

Related