Byte array to string in javascript

Converting byte array to string in javascript

But how do I get the functions working the other way?

Javascript Solutions

Solution 1 — Javascript

You need to parse each octet back to number, and use that value to get a character, something like this:

function bin2String(array) < var result = ""; for (var i = 0; i < array.length; i++) < result += String.fromCharCode(parseInt(array[i], 2)); > return result; > bin2String(["01100110", "01101111", "01101111"]); // "foo" // Using your string2Bin function to test: bin2String(string2Bin("hello world")) === "hello world"; 

Edit: Yes, your current string2Bin can be written more shortly:

function string2Bin(str) < var result = []; for (var i = 0; i < str.length; i++) result.push(str.charCodeAt(i).toString(2)); > return result; > 

But by looking at the documentation you linked, I think that the setBytesParameter method expects that the blob array contains the decimal numbers, not a bit string, so you could write something like this:

function string2Bin(str) < var result = []; for (var i = 0; i < str.length; i++) < result.push(str.charCodeAt(i)); > return result; > function bin2String(array) < return String.fromCharCode.apply(String, array); > string2Bin('foo'); // [102, 111, 111] bin2String(string2Bin('foo')) === 'foo'; // true 

Solution 2 — Javascript

Now, string ‘foo’ also equals String.fromCharCode(. [102, 111, 111])

Original answer

Simply apply your byte array to String.fromCharCode . For example

String.fromCharCode.apply(null, [102, 111, 111]) equals ‘foo’.

Caveat: works for arrays shorter than 65535 — MDN docs here.

Solution 3 — Javascript

Try the new Text Encoding API:

// create an array view of some valid bytes let bytesView = new Uint8Array([104, 101, 108, 108, 111]); console.log(bytesView); // convert bytes to string // encoding can be specfied, defaults to utf-8 which is ascii. let str = new TextDecoder().decode(bytesView); console.log(str); // convert string to bytes // encoding can be specfied, defaults to utf-8 which is ascii. let bytes2 = new TextEncoder().encode(str); // look, they're the same! console.log(bytes2); console.log(bytesView); 

Solution 4 — Javascript

String.fromCodePoint(. array) 

Solution 5 — Javascript

That string2Bin can be written even more succinctly, and without any loops, to boot!

function string2Bin ( str ) < return str.split("").map( function( val ) < return val.charCodeAt( 0 ); > ); > 

Solution 6 — Javascript

I think this would be more efficient:

function toBinString (arr) < var uarr = new Uint8Array(arr.map(function(x)return parseInt(x,2)>)); var strings = [], chunksize = 0xffff; // There is a maximum stack size. We cannot call String.fromCharCode with as many arguments as we want for (var i=0; i*chunksize < uarr.length; i++)< strings.push(String.fromCharCode.apply(null, uarr.subarray(i*chunksize, (i+1)*chunksize))); > return strings.join(''); > 

Solution 7 — Javascript

Even if I’m a bit late, I thought it would be interesting for future users to share some one-liners implementations I did using ES6.

One thing that I consider important depending on your environment or/and what you will do with with the data is to preserve the full byte value. For example, (5).toString(2) will give you 101 , but the complete binary conversion is in reality 00000101 , and that’s why you might need to create a leftPad implementation to fill the string byte with leading zeros. But you may not need it at all, like other answers demonstrated.

If you run the below code snippet, you’ll see the first output being the conversion of the abc string to a byte array and right after that the re-transformation of said array to it’s corresponding string.

// For each byte in our array, retrieve the char code value of the binary value const binArrayToString = array => array.map(byte => String.fromCharCode(parseInt(byte, 2))).join('') // Basic left pad implementation to ensure string is on 8 bits const leftPad = str => str.length < 8 ? (Array(8).join('0') + str).slice(-8) : str // For each char of the string, get the int code and convert it to binary. Ensure 8 bits. const stringToBinArray = str => str.split('').map(c => leftPad(c.charCodeAt().toString(2))) const array = stringToBinArray('abc') console.log(array) console.log(binArrayToString(array)) 

Solution 8 — Javascript

String to byte array: «FooBar».split(»).map(c => c.charCodeAt(0));

Byte array to string: [102, 111, 111, 98, 97, 114].map(c => String.fromCharCode(c)).join(»);

Solution 9 — Javascript

Too late to answer but if your input is in form of ASCII bytes, then you could try this solution:

function convertArrToString(rArr)< //Step 1: Convert each element to character let tmpArr = new Array(); rArr.forEach(function(element,index)< tmpArr.push(String.fromCharCode(element)); >); //Step 2: Return the string by joining the elements return(tmpArr.join("")); > function convertArrToHexNumber(rArr)< return(parseInt(convertArrToString(rArr),16)); > 

Solution 10 — Javascript

If you are using node.js you can do this:

yourByteArray.toString('base64'); 

Solution 11 — Javascript

Didn’t find any solution that would work with UTF-8 characters. String.fromCharCode is good until you meet 2 byte character.

For example Hüser will come as [0x44,0x61,0x6e,0x69,0x65,0x6c,0x61,0x20,0x48,0xc3,0xbc,0x73,0x65,0x72]

But if you go through it with String.fromCharCode you will have Hüser as each byte will be converted to a char separately.

Solution

Currently I’m using following solution:

function pad(n) < return (n.length < 2 ? '0' + n : n); > function decodeUtf8(data) < return decodeURIComponent( data.map(byte => ('%' + pad(byte.toString(16)))).join('') ); > 

Solution 12 — Javascript

I had some decrypted byte arrays with padding characters and other stuff I didn’t need, so I did this (probably not perfect, but it works for my limited use)

var junk = String.fromCharCode.apply(null, res).split('').map(char => char.charCodeAt(0) 127 && char.charCodeAt(0) >= 32 ? char : '').join(''); 

Solution 13 — Javascript

If your array is encoded in UTF-8 and you can’t use the TextDecoder API because it is not supported on IE:

1. You can use the FastestSmallestTextEncoderDecoder polyfill recommended by the Mozilla Developer Network website;
2. You can use this function also provided at the MDN website:

function utf8ArrayToString(aBytes) < var sView = ""; for (var nPart, nLen = aBytes.length, nIdx = 0; nIdx < nLen; nIdx++) nPart = aBytes[nIdx]; sView += String.fromCharCode( nPart > 251 && nPart < 254 && nIdx + 5 < nLen ? /* six bytes */ /* (nPart - 252 [++nIdx] - 128 [++nIdx] - 128 [++nIdx] - 128 [++nIdx] - 128 [++nIdx] - 128 : nPart > 247 && nPart < 252 && nIdx + 4 < nLen ? /* five bytes */ (nPart - 248 [++nIdx] - 128 [++nIdx] - 128 [++nIdx] - 128 [++nIdx] - 128 : nPart > 239 && nPart < 248 && nIdx + 3 < nLen ? /* four bytes */ (nPart - 240 [++nIdx] - 128 [++nIdx] - 128 [++nIdx] - 128 : nPart > 223 && nPart < 240 && nIdx + 2 < nLen ? /* three bytes */ (nPart - 224 [++nIdx] - 128 [++nIdx] - 128 : nPart > 191 && nPart < 224 && nIdx + 1 < nLen ? /* two bytes */ (nPart - 192 [++nIdx] - 128 : /* nPart < 127 ? */ /* one byte */ nPart ); > return sView; > let str = utf8ArrayToString([50,72,226,130,130,32,43,32,79,226,130,130,32,226,135,140,32,50,72,226,130,130,79]); // Must show 2H₂ + O₂ ⇌ 2H₂O console.log(str); 

Solution 14 — Javascript

> const stringToBin = (str) => [. str].map(item=>item.charCodeAt()) > undefined > stringToBin('hello') > (5) [104, 101, 108, 108, 111] > const binToString = (array) => String.fromCharCode(. array) > undefined > binToString(stringToBin('hello')) > 'hello' 

Solution 15 — Javascript

The simplest solution I’ve found is:

Источник

JavaScript — convert bytes array to string (UTF-8)

Blessing-D

In this short article, we would like to show, how to convert UTF-8 bytes array to string using JavaScript.

Practical examples

1. Custom solution

This example works under older web borsers and Node.js.

// ONLINE-RUNNER:browser; const getCode = (byte) => < const text = byte.toString(16); if (byte < 16) < return '%0' + text; >return '%' + text; >; const toString = (bytes) => < var result = ''; for (var i = 0; i < bytes.length; ++i) < result += getCode(bytes[i]); >return decodeURIComponent(result); >; // Usage example: const bytes = [83, 111, 109, 101, 32, 116, 101, 120, 116, 32, 104, 101, 114, 101, 46, 46, 46]; const string = toString(bytes); console.log(string);

const toString = (bytes) => < var result = ''; for (var i = 0; i < bytes.length; ++i) < const byte = bytes[i]; const text = byte.toString(16); result += (byte < 16 ? '%0' : '%') + text; >return decodeURIComponent(result); >;

2. Embedded solution

In this example, used solution appeard in major web browsers around 2014 and in Node.js v11.

// ONLINE-RUNNER:browser; const decoder = new TextDecoder('UTF-8'); const toString = (bytes) => < const array = new Uint8Array(bytes); return decoder.decode(array); >; // Usage example: const bytes = [83, 111, 109, 101, 32, 116, 101, 120, 116, 32, 104, 101, 114, 101, 46, 46, 46]; const string = toString(bytes); console.log(string);

See also

Alternative titles

Источник

Converting a Byte Array to String with Buffer in Node.JS

If you’re working with Node.JS, you may have encountered Buffer s which are a way to store binary data as a sequence of its bytes.

But what happens when you have serialised it, and you want to convert it back to a String?

Let us assume that we have the following data:

We can use Buffer.from to read in the bytes, and then return it as a String:

Written by Jamie Tanna on Mon, 20 Apr 2020 16:51:10 BST , and last updated on Wed, 02 Mar 2022 13:34:19 UTC .

Content for this article is shared under the terms of the Creative Commons Attribution Non Commercial Share Alike 4.0 International, and code is shared under the Apache License 2.0.

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Источник

JavaScript — convert bytes array to string (UTF-8)

Blessing-D

In this short article, we would like to show, how to convert UTF-8 bytes array to string using JavaScript.

Practical examples

1. Custom solution

This example works under older web borsers and Node.js.

// ONLINE-RUNNER:browser; const getCode = (byte) => < const text = byte.toString(16); if (byte < 16) < return '%0' + text; >return '%' + text; >; const toString = (bytes) => < var result = ''; for (var i = 0; i < bytes.length; ++i) < result += getCode(bytes[i]); >return decodeURIComponent(result); >; // Usage example: const bytes = [83, 111, 109, 101, 32, 116, 101, 120, 116, 32, 104, 101, 114, 101, 46, 46, 46]; const string = toString(bytes); console.log(string);

const toString = (bytes) => < var result = ''; for (var i = 0; i < bytes.length; ++i) < const byte = bytes[i]; const text = byte.toString(16); result += (byte < 16 ? '%0' : '%') + text; >return decodeURIComponent(result); >;

2. Embedded solution

In this example, used solution appeard in major web browsers around 2014 and in Node.js v11.

// ONLINE-RUNNER:browser; const decoder = new TextDecoder('UTF-8'); const toString = (bytes) => < const array = new Uint8Array(bytes); return decoder.decode(array); >; // Usage example: const bytes = [83, 111, 109, 101, 32, 116, 101, 120, 116, 32, 104, 101, 114, 101, 46, 46, 46]; const string = toString(bytes); console.log(string);

See also

Alternative titles

Источник