我来了

用ClientDataSet的时候，当ApplyUpdates成功，可由于其他表的错误导致事务回滚后，无法再次ApplyUpdates

Example:

 Database1.StrartTransaction;

 try

   ClientDataSet1.ApplyUpdates(0); //这句成功

   ClientDataSet2.ApplyUpdates(1); //这句出错

   Database1.Commit;

 except

   Database1.Rollback;

 end;

这时候ClientDataSet1的数据就无法再次ApplyUpdates了

***********************[red]解决方案[/red]*****************************

用下面这个控件吧，新加AS_ApplyUpdates和CommitUpdates

 Database1.StrartTransaction;

 try

   ClientDataSet1.AS_ApplyUpdates(0); //这句成功

   ClientDataSet2.AS_ApplyUpdates(1); //这句出错

   Database1.Commit;

 except

   Database1.Rollback;

   raise

 end;

 ClientDataSet1.CommitUpdates;

 ClientDataSet2.CommitUpdates;

现在可以了，只要不CommitUpdates永远可以AS_ApplyUpdates

______________________________Source________________________________________

unit CClientDataSet;

interface

uses Classes, Variants, SysUtils, DB, DBClient;

type

 TCClientDataSet = class(TClientDataSet)

 private

   FDeltaErrors: OleVariant;

 public

   function AS_ApplyUpdates(MaxErrors: Integer = 0): Integer;

   procedure CommitUpdates;

 end;

implementation

{ TCClientDataSet }

function TCClientDataSet.AS_ApplyUpdates(MaxErrors: Integer = 0): Integer;

var

 OwnerData: OleVariant;

begin

 CheckBrowseMode;

 if ChangeCount = 0 then

 begin

   Result := 0;

   FDeltaErrors := Null;

 end

 else begin

   if Assigned(BeforeApplyUpdates) then BeforeApplyUpdates(Self, OwnerData);

   FDeltaErrors := AppServer.AS_ApplyUpdates(ProviderName, Delta, MaxErrors, Result, OwnerData);

   if Assigned(AfterApplyUpdates) then AfterApplyUpdates(Self, OwnerData);

 end;

end;

procedure TCClientDataSet.CommitUpdates;

begin

 if VarIsEmpty(FDeltaErrors) then Exit;

   

 Reconcile(FDeltaErrors);

end;

end.