util.JSONObject.getLength
Returns the number of name-value pairs in the JSON object.
Syntax
util.JSONObject.getLength()
  RETURNS INTEGERUsage
The getLength() method returns the number of name-value
 pairs in the JSON object.
This method can be used along with the name() and
getType() methods to read the entries of a JSON object.
Example
IMPORT util
MAIN
    DEFINE obj util.JSONObject
    DEFINE i INTEGER
    LET obj = util.JSONObject.parse('{"id":123,"name":"Scott"}')
    FOR i=1 TO obj.getLength()
        DISPLAY i, ": ", obj.name(i), "=", obj.get(obj.name(i))
    END FOR
END MAINOutput:
          1: id=                  123.0
          2: name=Scott