The ToByteArray(s) command converts a Maple string to an array of bytes, that is, an object of type ByteArray. The resulting array is equivalent to one constructed using the expression Array( convert( s, 'bytes' ), 'datatype' = 'integer'[ 1 ], 'order' = 'C_order' ).

The FromByteArray(a) command converts a byte array to a string. The argument a must be a ByteArray. The string formed from the bytes in the array up to, but not including, the first zero entry (if any) is returned.

All of the StringTools package commands treat strings as (null-terminated) sequences of $8$-bit (ASCII) characters.  Thus, there is no support for multibyte character encodings, such as unicode encodings.

$\mathrm{with}\left(\mathrm{StringTools}\right)\:$

$a≔\mathrm{ToByteArray}\left(''foo''\right)$

$a≔\left[\begin{array}{ccc}102& 111& 111\end{array}\right]$

$\mathrm{lprint}\left(a\right)$

Array(1 .. 3,{1 = 102, 2 = 111, 3 = 111},datatype = integer[1],order = C_order)

$\mathrm{FromByteArray}\left(a\right)$

$''foo''$