770

I have a string, and I need to get its first character.

var x = 'somestring';
alert(x[0]); //in ie7 returns undefined

How can I fix my code?

Penny Liu
  • 15,447
  • 5
  • 79
  • 98
Simon
  • 22,637
  • 36
  • 92
  • 121

22 Answers22

1282

charAt can give wrong results for Unicode. Use Array.from:

Array.from('some string')[0];
Saeed Zhiany
  • 2,051
  • 9
  • 30
  • 41
Daniel Vandersluis
  • 91,582
  • 23
  • 169
  • 153
  • 15
    Worked on IE7, Chrome, Firefox. – Yuriy Faktorovich Aug 06 '10 at 19:39
  • 23
    `x.charAt()` will also return the first character as if no index is passed to this method, it will assume it to the `0`. – Mohammad Usman Jan 04 '18 at 12:05
  • 1
    @MohammadUsman While what you say is true, unfortunately charAt() without any parameters actually runs about 10x slower than chartAt(0) in Firefox as of Firefox 71. See for yourself here: https://jsperf.com/testing-the-first-character-in-a-string/1 – Stephen M Irving Dec 16 '19 at 21:54
  • 4
    This solution is good for ASCII, but it will break in all sorts of way as soon as you deal with more than that. `"".charAt(0)` returns `"\ud83d"`, `"café".charAt(3)` returns `e` and drops the accent, etc. https://stackoverflow.com/questions/38345372/why-is-an-emoji-string-length-2 has some info and a good alternative (use a library) – Clément May 30 '20 at 07:32
  • 4
    Also, to avoid confusion for future visitors: `x[0]` works just as well as `x.charAt(0)`, unless you care about IE 7 – Clément May 30 '20 at 07:37
  • @Clément Interesting your `é` is different than what you'd get on a keyboard, it is actually an e on the first code byte and just an accent on the second `'é'.charCodeAt(0) === 101 && 'é'.charCodeAt(1) === 769` `'é'.charCodeAt(0) === 233` – Tofandel May 14 '21 at 10:47
  • Not sure what you call "on a keyboard", but there's indeed a precomposed "é" in unicode that's different from "e" + combining accent. – Clément May 20 '21 at 22:03
  • Wow all the obscure techno-geekery. What's the best way to get a substring from a string? Are you absolutely, positively sure that there's not already a function designed to extract substrings, that understands strings, in the language, that we could be overlooking? – tekHedd Mar 31 '23 at 16:40
179

In JavaScript you can do this:

const x = 'some string';
console.log(x.substring(0, 1));
dota2pro
  • 7,220
  • 7
  • 44
  • 79
Dustin Laine
  • 37,935
  • 10
  • 86
  • 125
  • 10
    if prefer to use sub-string funcs, the `x.slice(0,1)` is shorter. And to get the last char simply use: `x.slice(-1)` – S.Serpooshan Oct 15 '18 at 05:59
  • 2
    "slice" is shorter as long as you don't think it's a waste to lose a few seconds of life every time you (or any other maintainer) read it and have to think about what it's actually supposed to achieve, every time you touch the code again. Forever. Just use the function that actually says what you are doing, you'll be happier 20 years from now when you're trying to fix the mess you made. #personalexperience – tekHedd Mar 31 '23 at 16:35
  • This should be the accepted answer. The whole "array" thing is cute and shows off casting strings to arrays and such but the question is, literally, "how do I get a one-character substring from the start of the string"; the obvious answer is to use the function called "substring". I mean. Elegance over flash. – tekHedd Mar 31 '23 at 16:37
  • @tekHedd "The whole 'array' thing is cute" no, the whole array thing is *correct*: basically all of the other solutions (charAt, substring, regex, bracket index) will not work as expected on non-ascii strings. Which may be *fine* for the use case at hand, but the array version will always work correctly. The other answers should *at least* mention the caveats. Although TBF it's not like the accepted answer mentions it either. – Jared Smith May 22 '23 at 12:36
  • @JaredSmith No, maybe you're thinking of python 2 or C. Javascript in this decade handles multibyte code points correctly. For example: "₳℮∑┌".substring(2) returns "∑┌". – tekHedd May 22 '23 at 18:31
  • @tekHedd not necessarily, `''.substring(0, 1)` does not yield the expected '', but destructuring does. – Jared Smith May 22 '23 at 19:11
122

You can use any of these.

There is a little difference between all of these So be careful while using it in conditional statement.

var string = "hello world";
console.log(string.slice(0,1));     //o/p:- h
console.log(string.charAt(0));      //o/p:- h
console.log(string.substring(0,1)); //o/p:- h
console.log(string.substr(0,1));    //o/p:- h
console.log(string[0]);             //o/p:- h
console.log(string.at(0));          //o/p:- h


var string = "";
console.log(string.slice(0,1));     //o/p:- (an empty string)
console.log(string.charAt(0));      //o/p:- (an empty string)
console.log(string.substring(0,1)); //o/p:- (an empty string)
console.log(string.substr(0,1));    //o/p:- (an empty string)
console.log(string[0]);             //o/p:- undefined
console.log(string.at(0));          //o/p:- undefined
Shailesh Sonare
  • 2,791
  • 1
  • 18
  • 14
37

Example of all method

First : string.charAt(index)

Return the caract at the index index

var str = "Stack overflow";

console.log(str.charAt(0));

Second : string.substring(start,length);

Return the substring in the string who start at the index start and stop after the length length

Here you only want the first caract so : start = 0 and length = 1

var str = "Stack overflow";

console.log(str.substring(0,1));

Alternative : string[index]

A string is an array of caract. So you can get the first caract like the first cell of an array.

Return the caract at the index index of the string

var str = "Stack overflow";

console.log(str[0]);
Alexis
  • 5,681
  • 1
  • 27
  • 44
  • Timing a single operation using console.time() is not a reasonable or accurate test of performance. Of COURSE there is no big difference between them when you only time a single operation. These methods do actually perform differently. – Stephen M Irving Dec 16 '19 at 21:57
34

const x = 'some string';
console.log(x.substring(0, 1));
dota2pro
  • 7,220
  • 7
  • 44
  • 79
Łukasz W.
  • 9,538
  • 5
  • 38
  • 63
17
var x = "somestring"
alert(x.charAt(0));

The charAt() method allows you to specify the position of the character you want.

What you were trying to do is get the character at the position of an array "x", which is not defined as X is not an array.

Eton B.
  • 6,121
  • 5
  • 31
  • 43
16

You can even use slice to cut-off all other characters:

x.slice(0, 1);
yckart
  • 32,460
  • 9
  • 122
  • 129
8
var str="stack overflow";

firstChar  = str.charAt(0);

secondChar = str.charAt(1);

Tested in IE6+, FF, Chrome, safari.

Tony Stark
  • 8,064
  • 8
  • 44
  • 63
Swathi
  • 323
  • 1
  • 4
  • 11
  • 12
    just curious, is there a reason you posted this answer? It seems to be a duplicate of the accepted answer. – Manatherin Nov 12 '12 at 23:57
  • 5
    They did give some extra info (even if it should have been a comment)... like what browsers it was tested in. I know `indexOf` doesn't work in IE8 and that's rather important to me. I actually started to google charAt compatibility until I saw this answer way down here. – gloomy.penguin Jul 25 '13 at 16:29
6

Try this as well:

x.substr(0, 1);
AmazingDayToday
  • 3,724
  • 14
  • 35
  • 67
  • substr() is considered a legacy function and should be avoided if at all possible. It is not actually a part of the JS language and could be removed at any time. Stay away from using substr() in all new code and old code should be refactored to use other methods. https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/substr – Stephen M Irving Dec 16 '19 at 22:02
4

Looks like I am late to the party, but try the below solution which I personally found the best solution:

var x = "testing sub string"
alert(x[0]);
alert(x[1]);

Output should show alert with below values: "t" "e"

DKS
  • 306
  • 1
  • 2
  • 16
2

x.substring(0,1)

Details

substring(start, end) extracts the characters from a string, between the 2 indices "start" and "end", not including "end" itself.

Special notes

  • If "start" is greater than "end", this method will swap the two arguments, meaning str.substring(1, 4) == str.substring(4, 1).
  • If either "start" or "end" is less than 0, it is treated as if it were 0.
Community
  • 1
  • 1
edelans
  • 8,479
  • 4
  • 36
  • 45
2

you can use in this way:

'Hello Mr Been'.split(' ').map( item => item.toUpperCase().substring(0, 1)).join(' ');
1

in Nodejs you can use Buffer :

let str = "hello world"
let buffer = Buffer.alloc(2, str) // replace 2 by 1 for the first char
console.log(buffer.toString('utf-8')) // display he
console.log(buffer.toString('utf-8').length) // display 2
Acolyte
  • 91
  • 1
  • 5
1

charAt() do not work if it has a parent prop
ex parent.child.chartAt(0)
use parent.child.slice(0, 1)

Penny Liu
  • 15,447
  • 5
  • 79
  • 98
Drew Cordano
  • 962
  • 9
  • 16
1

You can use any of the following :

let userEmail = "email";
console.log(userEmail[0]); // e
console.log(userEmail.charAt(0)); // e
console.log(userEmail.slice(0, 1)); // e
console.log(userEmail.substring(0, 1)); // e
console.log(userEmail.substr(0, 1)); // e
console.log(userEmail.split("", 1).toString()); // e
console.log(userEmail.match(/./)[0]); // e
Aboode
  • 11
  • 1
  • 2
0

It's been 10 years yet no answer mentioned RegExp.

var x = 'somestring';
console.log(x.match(/./)[0]);
GirkovArpa
  • 4,427
  • 4
  • 14
  • 43
0

Since every string is an array, probably the most succinct solution is by using the new spread operator:

const x = 'somestring'
const [head, ...tail] = x
console.log(head) // 's'

bonus is you can now access the total string but the first character using join('') on tail:

console.log(tail.join('')) // 'omestring'
shvahabi
  • 1,218
  • 10
  • 7
0

For any string str = "Hello World"

str.split(' ').map( item => item.toUpperCase().substring(0, 1)).join(' ');

Output: H W

Uzma
  • 299
  • 2
  • 5
0

There are many ways to find the string first character in Javascript. I think the easiest way to find is the string.charAt() method. This method takes an index number as a parameter and returns the index value. If you didn't give any parameter by default its returns the first character of the string.

 const str = "Bangladesh";
 const firstCharacter = str.charAt(0);
 const secondCharacter = str.charAt(1);
 console.log(firstCharacter)
 console.log(secondCharacter)
0

It's been 12 years and just one dev mentioned regexp, but it's a simpler way:

const str = 'string';

str.match(/\w/); // >> s

It will return the first character-class-word from the given string.

soujvnunes
  • 73
  • 1
  • 7
-1

in JQuery you can use: in class for Select Option:

$('.className').each(function(){
    className.push($("option:selected",this).val().substr(1));
});

in class for text Value:

$('.className').each(function(){
    className.push($(this).val().substr(1));
});

in ID for text Value:

$("#id").val().substr(1)
Amranur Rahman
  • 1,061
  • 17
  • 29
-1

You can use as well:

var x = "somestring";

console.log(x.split("")[0]); // output "s"

This should work with older browsers.

Alex
  • 1