How to convert from Hex
string to ASCII
string in JavaScript?
Ex:
32343630 it will be 2460
This question is related to
javascript
I found a useful function present in web3 library.
var hexString = "0x1231ac"
string strValue = web3.toAscii(hexString)
I've found that the above solution will not work if you have to deal with control characters like 02
(STX) or 03
(ETX), anything under 10
will be read as a single digit and throw off everything after. I ran into this problem trying to parse through serial communications. So, I first took the hex string received and put it in a buffer object then converted the hex string into an array of the strings like so:
buf = Buffer.from(data, 'hex');
l = Buffer.byteLength(buf,'hex');
for (i=0; i<l; i++){
char = buf.toString('hex', i, i+1);
msgArray.push(char);
}
Then .join it
message = msgArray.join('');
then I created a hexToAscii
function just like in @Delan Azabani's answer above...
function hexToAscii(str){
hexString = str;
strOut = '';
for (x = 0; x < hexString.length; x += 2) {
strOut += String.fromCharCode(parseInt(hexString.substr(x, 2), 16));
}
return strOut;
}
then called the hexToAscii
function on 'message'
message = hexToAscii(message);
This approach also allowed me to iterate through the array and slice into the different parts of the transmission using the control characters so I could then deal with only the part of the data I wanted. Hope this helps someone else!
You can use this..
var asciiVal = "32343630".match(/.{1,2}/g).map(function(v){_x000D_
return String.fromCharCode(parseInt(v, 16));_x000D_
}).join('');_x000D_
_x000D_
document.write(asciiVal);
_x000D_
An optimized version of the implementation of the reverse function proposed by @michieljoris (according to the comments of @Beterraba and @Mala):
function a2hex(str) {_x000D_
var hex = '';_x000D_
for (var i = 0, l = str.length; i < l; i++) {_x000D_
var hexx = Number(str.charCodeAt(i)).toString(16);_x000D_
hex += (hexx.length > 1 && hexx || '0' + hexx);_x000D_
}_x000D_
return hex;_x000D_
}_x000D_
alert(a2hex('2460')); // display 32343630
_x000D_
** for Hexa to String**
let input = '32343630';
Note : let output = new Buffer(input, 'hex'); // this is deprecated
let buf = Buffer.from(input, "hex");
let data = buf.toString("utf8");
For completeness sake the reverse function:
function a2hex(str) {
var arr = [];
for (var i = 0, l = str.length; i < l; i ++) {
var hex = Number(str.charCodeAt(i)).toString(16);
arr.push(hex);
}
return arr.join('');
}
a2hex('2460'); //returns 32343630
console.log(_x000D_
_x000D_
"68656c6c6f20776f726c6421".match(/.{1,2}/g).reduce((acc,char)=>acc+String.fromCharCode(parseInt(char, 16)),"")_x000D_
_x000D_
)
_x000D_
Another way to do it (if you use Node.js):
var input = '32343630';
const output = Buffer.from(input, 'hex');
log(input + " -> " + output); // Result: 32343630 -> 2460
Source: Stackoverflow.com