服务器上保存有上万条的基础数据，需要同步到全国各地的成千上万个客户端，而且这些基础数据也经常在有变化调整。这时候需要有一个稳定的数据同步程序，能分批同步基础数据，由于网络流量，网络的稳定性等因素，需要分批读取有更新过的数据，花费了半天时间写了一个例子代码，客户端同步从服务器上同步基础数据的功能，可以提供给大家参考一下，希望能有重复利用的价值。
// 1：打开业务数据库 SqLiteHelper dbHelper = new SqLiteHelper(BaseSystemInfo.BusinessDbConnection); // 2: 先保存个同步时间标志，什么时间成功同步过本地数据库？这样不用每次都同步所有的数据，只同步那个时间之后的数据就可以了。 BaseParameterManager parameterService = new BaseParameterManager(dbHelper, BaseSystemInfo.UserInfo); // 3：用参数的方式读取同步时间 string synchronous = parameterService.GetParameter("System", BaseOrganizeEntity.TableName, "Synchronous"); // 4: 传递参数用的，为了防注入漏洞的 List<KeyValuePair<string, object>> dbParameters = new List<KeyValuePair<string, object>>(); // 5：只获取有效的，未被删除的数据，（数据有被删除，也应该能同步才可以） string whereConditional = string.Empty; // string whereConditional = BaseOrganizeEntity.FieldDeletionStateCode + " = 0 AND " + BaseOrganizeEntity.FieldEnabled + " = 1 "; int recordCount = 0; int pageIndex = 1; // 网络情况好，客户端少，每次多获取一些数据，网络情况糟糕每次少获取一些数据 int pageSize = 500; // 6：不需要获取所有数据，在最大程度上减少网络上的数据流量 string selectField = BaseOrganizeEntity.FieldId + "," + BaseOrganizeEntity.FieldCode + "," + BaseOrganizeEntity.FieldFullName + "," + BaseOrganizeEntity.FieldEnabled + "," + BaseOrganizeEntity.FieldDeletionStateCode; int pageCount = 1; if (!string.IsNullOrEmpty(synchronous)) { DateTime modifiedOn = DateTime.Parse(synchronous); dbParameters.Add(new KeyValuePair<string, object>(BaseOrganizeEntity.FieldModifiedOn, modifiedOn)); if (!string.IsNullOrEmpty(whereConditional)) { whereConditional += " AND "; } // 7：只获取上次同步之后修改过的数据 whereConditional += BaseOrganizeEntity.FieldModifiedOn + " > " + DbHelper.GetParameter(BaseOrganizeEntity.FieldModifiedOn); } // 8：调用远程服务，获取需要同步的数据 DotNetService dotNetService = new DotNetService(); DataTable dtSynchronous = dotNetService.UserCenterDbHelperService.GetDataTableByPage(BaseSystemInfo.UserInfo, out recordCount, BaseOrganizeEntity.TableName, selectField, pageIndex, pageSize, whereConditional, dbParameters, BaseOrganizeEntity.FieldId); // 9：防止网络连接超时，把网络连接释放掉 if (dotNetService.UserCenterDbHelperService is ICommunicationObject) { ((ICommunicationObject)dotNetService.UserCenterDbHelperService).Close(); } // 取得总页数 if (recordCount % pageSize == 0) { pageCount = recordCount / pageSize; } else { pageCount = recordCount / pageSize + 1; } BaseOrganizeManager organizeManager = null; // 10：按每页进行循环获取，也防止数据库连接超时，网络连接超时，每次获取一部分数据 while (dtSynchronous != null && dtSynchronous.Rows.Count > 0) { BaseOrganizeEntity organizeEntity = null; // 11：防止本地数据库连接超时，每次重新打开一个数据库连接，这样保险一些 organizeManager = new BaseOrganizeManager(dbHelper, BaseSystemInfo.UserInfo); foreach (DataRow dr in dtSynchronous.Rows) { // 12：不用实体化其实也可以的，先实体化吧，代码规范一些 organizeEntity = new BaseOrganizeEntity(); organizeEntity.Id = int.Parse(dr[BaseOrganizeEntity.FieldId].ToString()); organizeEntity.Code = dr[BaseOrganizeEntity.FieldCode].ToString(); organizeEntity.FullName = dr[BaseOrganizeEntity.FieldFullName].ToString(); organizeEntity.Enabled = int.Parse(dr[BaseOrganizeEntity.FieldEnabled].ToString()); organizeEntity.DeletionStateCode = int.Parse(dr[BaseOrganizeEntity.FieldDeletionStateCode].ToString()); // 13: 先按更新操作。 SQLBuilder sqlBuilder = new SQLBuilder(dbHelper); sqlBuilder.BeginUpdate(BaseOrganizeEntity.TableName); sqlBuilder.SetValue(BaseOrganizeEntity.FieldCode, organizeEntity.Code); sqlBuilder.SetValue(BaseOrganizeEntity.FieldFullName, organizeEntity.FullName); sqlBuilder.SetValue(BaseOrganizeEntity.FieldEnabled, organizeEntity.Enabled); sqlBuilder.SetValue(BaseOrganizeEntity.FieldDeletionStateCode, organizeEntity.DeletionStateCode); sqlBuilder.SetWhere(BaseOrganizeEntity.FieldId, organizeEntity.Id); if (sqlBuilder.EndUpdate() == 0) { // 14: 若没找到数据，进行插入操作。 sqlBuilder.BeginInsert(BaseOrganizeEntity.TableName); sqlBuilder.SetValue(BaseOrganizeEntity.FieldId, organizeEntity.Id); sqlBuilder.SetValue(BaseOrganizeEntity.FieldCode, organizeEntity.Code); sqlBuilder.SetValue(BaseOrganizeEntity.FieldFullName, organizeEntity.FullName); sqlBuilder.SetValue(BaseOrganizeEntity.FieldEnabled, organizeEntity.Enabled); sqlBuilder.SetValue(BaseOrganizeEntity.FieldDeletionStateCode, organizeEntity.DeletionStateCode); sqlBuilder.EndInsert(); } // 15: 这个代码是按实体进行更新同步的代码例子。 // 若有缺少字段什么的，也闹心 // if (organizeManager.UpdateObject(organizeEntity) == 0) // { // organizeManager.AddObject(organizeEntity); // } } // 16: 看是否有必要继续获取数据，判断页数，若没必要能少循环一次就少循环一次 dtSynchronous = null; if (pageIndex < pageCount) { // 17: 若数据没获取好，继续获取数据 pageIndex++; dotNetService = new DotNetService(); dtSynchronous = dotNetService.UserCenterDbHelperService.GetDataTableByPage(BaseSystemInfo.UserInfo, out recordCount, BaseOrganizeEntity.TableName, selectField, pageIndex, pageSize, whereConditional, dbParameters, BaseOrganizeEntity.FieldId); if (dotNetService.UserCenterDbHelperService is ICommunicationObject) { ((ICommunicationObject)dotNetService.UserCenterDbHelperService).Close(); } } } // 18: 更新数据库中的同步时间标志。 parameterService.SetParameter("System", BaseOrganizeEntity.TableName, "Synchronous", DateTime.Now.ToString(BaseSystemInfo.DateTimeFormat));