libsbml.SBMLReader.readSBML C# (CSharp) Method

        public SBMLDocument readSBML(string filename)
        {
            IntPtr cPtr = libsbmlPINVOKE.SBMLReader_readSBML(swigCPtr, filename);
            SBMLDocument ret = (cPtr == IntPtr.Zero) ? null : new SBMLDocument(cPtr, true);
            return ret;
        }

 public void TestAll()
 {
     SBMLReader reader = new SBMLReader();
     SBMLDocument document = reader.readSBML(TestConstant.SBML_BIOMD0000000003);
     Model sbmlModel = document.getModel();
     // Set FunctionDefinition
     ASTNode math = libsbml.libsbml.parseFormula("V0 * 5");
     FunctionDefinition fd = sbmlModel.createFunctionDefinition();
     fd.setId("FD");
     fd.setName("FD");
     fd.setMath(math);
     // Set Event
     Event ev = sbmlModel.createEvent();
     ev.setId("Event");
     ev.setName("Event");
     ev.setTrigger(new Trigger(2,3));
     EventAssignment ea = ev.createEventAssignment();
     ea.setId("Assignment");
     ea.setName("Assignment");
     // Set Initial Amount
     InitialAssignment ia = sbmlModel.createInitialAssignment();
     ia.setSymbol("M1");
     ia.setMath(math);
     // Set UnitDefinition
     UnitDefinition ud = sbmlModel.createUnitDefinition();
     ud.setId("UD");
     ud.setName("UD");
     Unit unit = ud.createUnit();
     unit.setId("Unit");
     unit.setName("Unit");
     //
     SBML_Model model = new SBML_Model(sbmlModel);
 }