Ruby: create a String from bytes

Question

I would like to build a string from a byte value.

I currently use:

str = \" \"
str[0] = byte

This seems to work fine but I find it

Answer 1

for 1.9 you need:

[195,164].pack('c*').force_encoding('UTF-8')

Answer 2

There is a much simpler approach than any of the above: Array#pack:

>> [65,66,67,68,69].pack('c*')
=>  "ABCDE"

I believe pack is implemented in c in matz ruby, so it also will be considerably faster with very large arrays.

Also, pack can correctly handle UTF-8 using the 'U*' template.

Answer 3

If bytes is an array of Fixnum's you could try this:

bytes.map {|num| num.chr}.join

or this:

s = ''
bytes.each {|i| s << i}

Answer 4

can't remember if there is a single function that does that:

>> a = [65,66,67]
=> [65, 66, 67]
>> a.map {|x| x.chr}.join
=> "ABC"

Answer 5

This isn't the OP's question, but if you have just a single byte (not in an array) and want to make a string out of it, use chr

c = 65
=> 65
c.chr
=> "A"
c.chr.class
=> String