开发者

JavaScript access string chars as array

Is it ok to do this:

var myString="Hello!";
alert(myString[0]); // shows "H" in an alert win开发者_如何学Cdow

Or should it be done with either charAt(0) or substr(0,1)? By "is it ok" I mean will it work on most browsers, is there a best practice recommandation that says otherwise etc.

Thank you.


Accessing characters as numeric properties of a string is non-standard prior to ECMAScript 5 and doesn't work in all browsers (for example, it doesn't work in IE 6 or 7). You should use myString.charAt(0) instead when your code has to work in non-ECMAScript 5 environments. Alternatively, if you're going to be accessing a lot of characters in the string then you can turn a string into an array of characters using its split() method:

var myString = "Hello!";
var strChars = myString.split("");
alert(strChars[0]);


Using charAt is probably the best idea since it conveys the intent of your code most accurately. Calling substr for a single character is definitely an overkill.

alert(myString.charAt(0));


2018 answer: Yes it is OK to access strings like arrays.

The syntax is clear and concise. IE6 and IE7 are long gone. I see no reason not to use it.


In ES6 we can use destructuring since a string can be treated as an array:

const [...rest] = 'Hello!';

console.log(rest)
> Array ["H", "e", "l", "l", "o", "!"]

console.log(rest[0])
> "H"
0

上一篇:

下一篇:

精彩评论

暂无评论...
验证码 换一张
取 消

最新问答

问答排行榜