Update Process Instance data field value through worklistitem

Hi All,

This is what I am trying to do:

SourceCode.Workflow.Client.Connection con = new Connection(); 

            con.Open("AKSGAKJH"); 
            Worklist wl = con.OpenWorklist("ASP","satya"); 
            foreach (WorklistItem wli in wl) 
            { 
                wli.Open(); 
                 wli.ProcessInstance.DataFields["Outcome"] .Value= "Approve";  // this is read only as suggested in K2 designer for Visual Studio

                 wli.Update();
                  wli.Actions["Approve"].Execute(); 
                
            } 
            con.Close();

But it sounds strange that , I am not able to assign value to a process instance datafield through worklist item . It seems it is read only.

I remember in K2.NET 2003 , it was possible to  update data field through worklistitem object.

Please guide.

Thanks ,

Satya