Procedure TOPCClient.ReadAllItems;
 var
 I: Integer;
 ItemRead : Boolean;
 Name : String;
 OPCUAResult: _UAAttributeDataResult;
 OPCUAResults: OleVariant;
 J,K: Cardinal;
 
 begin
   try
     if (Connected) then begin
        if (FirstCylyle) then begin
         for J := 0 to Length(OPCServerItemArray)-1 do begin
           Name := OPCServerItemArray[J].Source + '.' + OPCServerItemArray[J].ItemName;
           ReadOPCUAArguments[J] := CoUAReadArguments.Create;
           ReadOPCUAArguments[J].ReadParameters.MaximumAge := 100;
           ReadOPCUAArguments[J].EndpointDescriptor.UrlString := Url_String;
           ReadOPCUAArguments[J].NodeDescriptor.NodeId.ExpandedText := 'nsu='+ nsu + ';s=' + S0 + '.' + Name;
         end;
         OPCUAArguments := VarArrayCreate([0, Length(OPCServerItemArray)-1], varVariant);
         for I := 0 to Length(OPCServerItemArray)-1 do begin
           OPCUAArguments[I] := ReadOPCUAArguments[I];
         end;
         FirstCylyle := False;
       end;
       // Perform the operation
       TVarData(OPCUAResults).VType := varArray or varVariant;
 
       //OPCLabs 2019.2 Version
       //TVarData(OPCUAResults).VArray := PVarArray(OPCUAClientRead.ReadMultiple(OPCUAArguments));
 
       //OPCLabs 2019.1 Version
       {TVarData(OPCUAResults).VArray := PVarArray(OPCUAClientRead.ReadMultiple(
       PSafeArray(TVarData(OPCUAArguments).VArray)));}
 
       //OPCLabs 2023.1 Version
       TVarData(OPCUAResults).VArray := PVarArray(OPCUAClientRead.ReadMultiple(OPCUAArguments));
 
       // Writing the results in Delphi internal Array
       try
         for K := VarArrayLowBound(OPCUAResults, 1) to VarArrayHighBound(OPCUAResults, 1) do
           begin
             OPCUAResult := IInterface(OPCUAResults[K]) as _UAAttributeDataResult;
             OPCServerItemArray[K].Value    := OPCUAResult.AttributeData.value;
             OPCServerItemArray[K].ItemQuality := OPCUAResult.AttributeData.StatusCode.IsGood;
             OPCServerItemArray[K].TimeStamp := OPCUAResult.AttributeData.ServerTimestampLocal;
           end;
           OPCStatus_Good := True;
       except
         on E: Exception do begin
           OPCStatus_Good := False;
           Meldung(1,'TOPCClient.ReadAllItems - Exception: writing into Delphi-Intern Array ' + E.Message);
         end;
       end;;
 
     end else begin
       Meldung(0,'TOPCClient.ReadAllItems: (Not connected to the OPC UA Server!)');
     end;
   except
     on E: Exception do begin
       Meldung(0,'TOPCClient.ReadAllItems - Exception: ' + E.Message);
     end;
   end;
 end;

Procedure TOPCClient.WriteMultipleItems_DT;
Var
  I : Integer;
  Results : OleVariant;
  ExpandedText_DT : WideString;
  WriteArguments_DT: OleVariant;
 
begin
  try
    if (connected) then begin
      if (Write_DT_Variables) then begin
        for I := 0 to WriteMultipleIdx_DT-1 do begin
          if (FirstCycleWrite_DT) then begin
            WriteValueArguments_DT[I] := CoUAWriteValueArguments.Create;
            WriteValueArguments_DT[I].EndpointDescriptor.UrlString := Url_String;
          end;
          ExpandedText_DT := 'nsu='+ nsu + ';s=' + S0 + '.' + WriteToOPCServerArray_DT[I].Source + '.' + WriteToOPCServerArray_DT[I].ItemName;
          WriteValueArguments_DT[I].NodeDescriptor.NodeId.ExpandedText := ExpandedText_DT;
          WriteValueArguments_DT[I].Value := WriteToOPCServerArray_DT[I].Value;
        end;
        FirstCycleWrite_DT := False;
        WriteArguments_DT := VarArrayCreate([0, WriteMultipleIdx_DT-1], varVariant);
        for I := 0 to WriteMultipleIdx_DT-1 do begin
          WriteArguments_DT[I] := WriteValueArguments_DT[I];
        end;
 
        try
          TVarData(Results).VType := varArray or varVariant;
 
          //OPCLabs 2019.1 Version
          {TVarData(Results).VArray := PVarArray(OPCUAClientMultiWrite_DT.WriteMultipleValues(
          PSafeArray(TVarData(WriteArguments_DT).VArray)));}
 
          //OPCLabs 2023.1 Version
          TVarData(Results).VArray := PVarArray(OPCUAClientMultiWrite_DT.WriteMultipleValues(WriteArguments_DT));
          VarClear(Results);
          VarClear(WriteArguments_DT);
          Write_DT_Variables := False;
        except
          on E: EOleException do
          begin
             Meldung(0,'EOleException in TOPCClient.WriteMultipleItems_DT: ' + E.GetBaseException.Message);
          end;
        end;
      end;
 
    end else begin
      Meldung(0,'TOPCClient.WriteMultipleItems_DT: not connected to the OPC UA Server');
    end;
  except
    on E: Exception do begin
      Meldung(0,'TOPCClient.WriteMultipleItems_DT - Exception: ' + E.Message);
    end;
  end;
end;