How I can split a varchar2 in stored function

[oceanju]

in comma_to_table, must the delimiter be the ","? If the there is a "," in the string? How I can do?
for example:
the sourse string: '12,34|23,34|34,23|'
if I replace "|" to ",", the string will convert to '12,34,23,34,34,23'.
The reason why I use the '|' as the delimiter is the '|' can not in the item.
please help.
thanks