Using unpack to write a byte array with hex characters?

Question

I want to take a value like:

ff0000

and make it into a byte array containing those hex values:

\xff\x00\x00

I'm not clear on how to do this using str.unpack

Bob Aman · Accepted Answer · 2009-10-15 17:52:53Z

4

"ff0000".scan(/../).map { |match| match.hex } #=> [255, 0, 0]

or

("ff0000".scan(/../).map { |match| match.hex }).pack('C*') #=> "\377\000\000"

Depending on what format you want it in.

answered Oct 15, 2009 at 17:52

Bob Aman

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Comments

wdebeaum · Accepted Answer · 2009-10-15 17:45:45Z

3

I'm not sure unpack can do this. Try this instead:

"ff0000".gsub(/../) { |match| match.hex.chr }

answered Oct 15, 2009 at 17:38

wdebeaum

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