Serializing PSON object to JSON string

if I have a PSON object something like this:

pson object;
object["key1"] = 55;
object["key2"] = true;
object["key3"] = "hello";
object["key4"] = 3.14;

and I want to convert it to a JSON string so I can to post it to a web URL…

is there any way to do that? because all I didn’t found it in the Protoson docs ( there is only one method for Serialization and deserialization which used virtual classes that provided methods for writing and reading bytes.

is there any way to do this?