Convert string to Uint8Array in javascript

Question

I have a string "ab05d705" and I am trying to convert it to the following so I can add it to a Uint8Array. So how do I convert the string "ab05d705" to

0xab,0x05,0xd7,0x05 

to put into the following

var data = new Uint8Array([0xab,0x05,0xd7,0x05]); 

Any help would be so appreciated.

Answer 1

You can use the Web API TextEncoder to get a Uint8Array of UTF-8 bytes from a string:

const encoded = new TextEncoder().encode('€')
console.log(encoded) // Uint8Array(3) [226, 130, 172]

Answer 2

A Uint8Array is basically an array full of charcodes, so you could split all the characters and convert them to charcodes, and then using that array and calling Uint8Array.from on it. Something like this should work:

var string = "Hello World!"
var uint8 = Uint8Array.from(string.split("").map(x => x.charCodeAt()))

Answer 3

If you are coming from the future Buffer.from(string, encoding) is probably the best option.

const uint: Uint8Array = Buffer.from('string here', 'base64')

Answer 4

try this:

var s = "ab05d705";
var result = [];

for(var i = 0; i < s.length; i+=2)
{
    result.push(parseInt(s.substring(i, i + 2), 16));
}
result = Uint8Array.from(result)
console.log(result);

parseInt(value, base) creates a JS number combining the input and given base - we're using base 16 in this case.