（急求）SQLDMO在C#中的差异备份还原有关问题

    SQLDMO.Restore oRestore = new SQLDMO.RestoreClass();//创建还原对象    SQLDMO.SQLServer oSQLServer = new SQLDMO.SQLServerClass();//创建服务对象    try    {        oSQLServer.LoginSecure = false;        oSQLServer.Connect("localhost\\sqlexpress", "sa", "sa");//连接数据服务        SQLDMO.QueryResults qr = oSQLServer.EnumProcesses(-1);//查询该数据库正在连接的进程        int iColPIDNum = -1;        int iColDbName = -1;        for (int i = 1; i <= qr.Columns; i++)        {            string strName = qr.get_ColumnName(i);            if (strName.ToUpper().Trim() == "SPID")            {                iColPIDNum = i;            }            else if (strName.ToUpper().Trim() == "DBNAME")            {                iColDbName = i;            }            if (iColPIDNum != -1 && iColDbName != -1)                break;        }        for (int i = 1; i <= qr.Rows; i++)        {            int IPID = qr.GetColumnLong(i, iColPIDNum);            string strDbName = qr.GetColumnString(i, iColDbName);            if (strDbName.ToUpper().Trim() == "mm_gis_intmap".ToUpper())            {                oSQLServer.KillProcess(IPID);//kill正在连接的进程            }        }        oRestore.Action = SQLDMO.SQLDMO_RESTORE_TYPE.SQLDMORestore_Database;        oRestore.Database = "mm_gis_intmap";        oRestore.Files = @"C:\mm_gis_intmap\mmgt_t.bak";//设置数据备份文件，如果该文件是完全备份，运行OK，差异备份即不行        //oRestore.StandbyFiles = @"C:\mm_gis_intmap\mmgt_t1.bak";        oRestore.FileNumber = 1;        oRestore.ReplaceDatabase = true;        oRestore.SQLRestore(oSQLServer);    }    catch    {        throw;    }    finally    {        oSQLServer.DisConnect();    }