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From: Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups: comp.lang.javascript
Subject: Re: How do I convert the following to Uint8Array.
Date: Fri, 22 Jan 2016 12:54:38 +0000
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Stefan Weiss <krewecherl@gmail.com> writes:

> On 01/22/2016 13:25, Stefan Weiss wrote:
>> On 01/22/2016 12:52, Robby Balona wrote:
>>> 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]);
>> 
>> As a one-liner:
>> 
>>   str.match(/.{2}/g).map(function (hex) { return parseInt(hex, 16); })
>
> Actually, that didn't answer your question completely. To create a
> Uint8Array from your string, you can use:
>
>   var str = "ab05d705";
>   var arr = Uint8Array.from(
>     str.match(/../g).map(function (hex) { return parseInt(hex, 16); })
>   );

I didn't think of using match -- much nicer!  You can avoid using map if
you like because 'from' allows for a mapping function:

  Uint8Array.from(s.match(/../g), d => parseInt(d, 16))

or even

  Uint8Array.from(s.match(/../g), d => '0x'+d)

but I think the explicit parseInt is more helpful.

-- 
Ben.