protected override void Execute(CodeActivityContext context)
{
IWorkflowContext workflowContext = context.GetExtension <IWorkflowContext>();
ParameterStack pstack = context.GetValue <ParameterStack>(this.Parameter);
string distKey = context.GetValue <string>(this.DistKey);
string srcKey = context.GetValue <string>(this.SrcKey);
var obj = pstack.GetValue(srcKey, false);
pstack.SetValue(distKey, obj);
pstack.ClearKey(srcKey);
}