使用clientdataset Reconcile 出错，请问这里的代码有什么错。

Question

if not varisnull(mastervar) then
     qidata.xldclient.Reconcile(mastervar) else    这里出错
 if not varisnull(detailvar1) then
     qidata.liylclient.Reconcile(detailvar1) else   
 if not varisnull(detailvar2) then
      qidata.fyClient.Reconcile(detailvar2) else
 if not varisnull(detailvar3) then
     qidata.xltypeitemclient.Reconcile(detailvar3) else
   begin
       qidata.xldclient.Reconcile(mastervar);
        qidata.liylclient.Reconcile(detailvar1);    
        qidata.xltypeitemclient.Reconcile(detailvar3);
        qidata.fyClient.Reconcile(detailvar2);
      //  qidata.xldclient.MergeChangeLog;
      //  qidata.liylclient.MergeChangeLog;
      //  qidata.fyClient.MergeChangeLog;
      //  qidata.xltypeitemclient.MergeChangeLog;
        qidata.xldclient.Refresh;
        qidata.liylclient.Refresh;
        qidata.fyClient.refresh;
        qidata.xltypeitemclient.Refresh;
    end;
错误代码  ‘mismadtch  datapacket';