Array to string in JavaScript

Question

I get an array of numbers as a response from remote command execution (using ssh2). How do I convert it to a string?

[97,112,112,46,106,115,10,110,111,100,101,46,106,115,10]

• jillro: You mean converting each number to the corresponding ASCII character ?
• Ash: possible duplicate of Convert character to ASCII code in Javascript
• Bali Balo: @Ashish Nope. Actually it's the opposite.
• Ash: @Bali Balo,Ya right ! but in that, this is also define that how to do the same.
• Ash: read @Török Gábor comment in that question.

Answer 1

var result = String.fromCharCode.apply(null, arrayOfValues);

JSFiddle

Explanations:

String.fromCharCode can take a list of char codes as argument, each char code as a separate argument (for example: String.fromCharCode(97,98,99)).

apply allows to call a function with a custom this, and arguments provided as an array (in contrary to call which take arguments as is). So, as we don't care what this is, we set it to null (but anything could work).

In conclusion, String.fromCharCode.apply(null, [97,98,99]) is equivalent to String.fromCharCode(97,98,99) and returns 'abc', which is what we expect.

Answer 2

It depends on what you want and what you mean.

Option One: If you want to convert the text to ASCII, do this:

var theArray = [97,112,112,46,106,115,10,110,111,100,101,46,106,115,10];
theString = String.fromCharCode.apply(0, theArray);

(Edited based on helpful comments.)

Produces:

app.js
node.js

Option Two: If you just want a list separated by commas, you can do .join(','):

var theArray = [97,112,112,46,106,115,10,110,111,100,101,46,106,115,10];
var theString = theArray.join(',');

You can put whatever you want as a separator in .join(), like a comma and a space, hyphens, or even words.

• dandavis: String.fromCharCode.apply(0, [97,112,112,46,106,115,10,110,111,100,101,46,106,115,10]) avoids un-needed looping and vars, is less to type, and faster to execute. ed: looks like Bali Jinxed me...

Answer 3

In node.js it's usually done with buffers:

> new Buffer([97,112,112,46,106,115,10,110,111,100,101,46,106,115,10]).toString()
'app.js\nnode.js\n'

It'll be faster than fromCharCode, and what's most important, it'll preserve utf-8 sequences correctly.

• Mark Birbeck: Yes, definitely the right way to go in Node. Note that new Buffer is deprecated, though, and that you should use Buffer.from(array).toString().

Answer 4

just use the toString() function:

var yourArray = [97,112,112,46,106,115,10,110,111,100,101,46,106,115,10];
var strng = yourArray.toString();

• Kuri: Yeah, it worked for me. Actually it is in w3schools: w3schools.com/jsref/jsref_tostring_array.asp
• elixenide: I just tried it again; something was wrong with my console, apparently. It "works," but merely produces the text 97,112,112,46,106,115,10,110,111,100,101,46,106,115,10. It looks like OP wants the ASCII values of those numbers, not the list.
• elixenide: Also, w3schools is not a good resource. Despite its name, it is in no way official, authoritative, or associated with the W3C. In fact, it's notorious for spreading incorrect and obsolete information.

Answer 5

The ssh2 module passes a Buffer (not an actual javascript array) to 'data' event handlers for streams you get from exec() or shell(). Unless of course you called setEncoding() on the stream, in which case you'd get a string with the encoding you specified.

If you want the string representation instead of the raw binary data, then call chunk.toString() for example.