This function returns a copy of str,
translating all occurrences of each character in
from to the corresponding character in
to.
If from and to are
different lengths, the extra characters in the longer of the two
are ignored.
strtr() may be called with only two
arguments. If called with two arguments it behaves in a new way:
from then has to be an array that contains
string -> string pairs that will be replaced in the source
string. strtr() will always look for the
longest possible match first and will *NOT* try to replace stuff
that it has already worked on.
Note: This optional
toandfromparameters were added in PHP 4.0.0
See also ereg_replace().