場景

新建一個程序，需要對數據的表進行查詢并將查詢結果轉換為實體類，然后將多個實體類

再插入到另一個數據庫的表中，執行插入的過程中要使用事務。

注：

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https://blog.csdn.net/badao_liumang_qizhi
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實現

不帶事務只是查詢

//儲存數據的工具初始化DataSet idxDs = new DataSet();//constr：數據庫連接字符串配置stringconstr="server=localhost;database=Badao;uid=sa;pwd=123";using (SqlConnection conn=new SqlConnection(constr)){conn.Open();Console.WriteLine("開始查詢索引數據...");//查詢索引數據string idxSql = "SELECT * FROM Idx1_1";//獲取sql語句SqlDataAdapter idxSda = new SqlDataAdapter(idxSql, conn);?? //(查詢語句和連接工具)idxSda.Fill(idxDs);??? //將適配器數據存入DataSet工具中}

注：

首先聲明一個DataSet用來存儲執行查詢的結果，然后使用連接數據的字符串打開連接。

然后使用Adapter執行sql語句，將查詢結果填充到Dataset中。

怎樣將查詢結果與實體類對應賦值

??????????????? IdxRecord idx = null;Console.WriteLine("開始儲存索引數據...");foreach (DataRow row in idxDs.Tables[0].Rows){idx = new IdxRecord();idx.IdxID = DataProcessor.RowValue(row, "Idx_ID", 0);idx.DataPoint = DataProcessor.RowValue(row, "Data_Point", 0);idx.ScheduleIndex = DataProcessor.RowValue(row, "Schedule_Index", 0L);?????????????????idxList.Add(idx);}

注：

聲明一個實體類，其中要有與數據庫列所對應的字段。

然后將DataSet中的內容與實體列的屬性一一賦值。

最后將實體類對象添加到實體類的list上。

其中DataProcessor.RowValue是一個工具類中的方法，此方法中的第二個參數是對應的數據庫中的列

?public static short RowValue(DataRow dr, string field, short defaultValue){short Result = defaultValue;if (dr.Table.Columns.Contains(field)){if (dr[field] != null && dr[field] != DBNull.Value){if (short.TryParse(dr[field].ToString(), out Result)){return Result;}}}else{Console.WriteLine("DataTable中不存在[" + field + "]列!");}return defaultValue;}

怎樣開啟事務并存入數據

??????????? //存入bak數據庫stringconstrBak="server=localhost;database=BadaoBak;uid=sa;pwd=123";using (SqlConnection conn = new SqlConnection(constrBak))//constr：數據庫連接配置{conn.Open();//開啟事務SqlTransaction trans = conn.BeginTransaction();SqlCommand cmd = new SqlCommand();cmd.Connection = conn;//添加連接工具cmd.Transaction = trans;//添加事務try{cmd.CommandText = "INSERT INTO idx1_1 values? ('" + idx.IdxID + "','" + idx.StepEnd +"')";//添加sql語句cmd.ExecuteNonQuery();//執行Console.WriteLine("插入索引數據成功");trans.Commit();//執行完成之后提交}catch (Exception e){//執行sql語句失敗，事務回滾trans.Rollback();}finally{conn.Close();}}

完整示例代碼

?public static void Main(string[] args){List<IdxRecord> idxList = null;???????? //索引數據//儲存數據的工具初始化DataSet idxDs = new DataSet();//constr：數據庫連接字符串配置string constr = "server=localhost;database=Badao;uid=sa;pwd=123";using (SqlConnection conn=new SqlConnection(constr)){conn.Open();Console.WriteLine("開始查詢索引數據...");//查詢索引數據string idxSql = "SELECT * FROM Idx1_1";//獲取sql語句SqlDataAdapter idxSda = new SqlDataAdapter(idxSql, conn);?? //(查詢語句和連接工具)idxSda.Fill(idxDs);??? //將適配器數據存入DataSet工具中idxList = new List<IdxRecord>();IdxRecord idx = null;Console.WriteLine("開始儲存索引數據...");foreach (DataRow row in idxDs.Tables[0].Rows){idx = new IdxRecord();idx.IdxID = DataProcessor.RowValue(row, "Idx_ID", 0);idxList.Add(idx);}Console.WriteLine("儲存索引數據成功，成功儲存數量為：" + idxList.Count);Console.WriteLine("查詢索引數據成功");Console.WriteLine("開始根據索引數據查詢記錄數據...");//在循環中根據索引數據查詢記錄數據for (int i = 0; i+1 < idxList.Count;i++){List<Record> recordList = new List<Record>();List<List<AuxRecord>> autxRecordsList = new List<List<AuxRecord>>();for (int k = idxList[i].DataPoint; k < idxList[i + 1].DataPoint;k++ ){DataSet recordsDs = new DataSet();DataSet auxTDs = new DataSet();//查詢 記錄數據string recordSql = "SELECT * FROM WsC1_1 where Data_Point =" + k;//獲取sql語句//Console.WriteLine("開始執行的查詢語句為：" + recordSql);SqlDataAdapter recordsSda = new SqlDataAdapter(recordSql, conn);?? //(查詢語句和連接工具)recordsSda.Fill(recordsDs);??? //將適配器數據存入DataSet工具中Record entity = new Record();DataRow row = recordsDs.Tables[0].Rows[0];entity.DataPoint = DataProcessor.RowValue(row, "Data_Point", 0);entity.ScheduleIndex = DataProcessor.RowValue(row, "Schedule_Index", 0L);recordList.Add(entity);//Console.WriteLine("根據索引數據的DataPoint：" + k + "查詢到的記錄數據的DataPoint:" + entity.DataPoint);//根據索引數據查詢輔助通道溫度數據Console.WriteLine("開始根據記錄數據查詢輔助通道溫度數據....");List<AuxRecord> autxRecords = new List<AuxRecord>();???????? //輔助通道溫度數據string AuxTSql = "SELECT * FROM Aux1_1_25 where IvIndex =" + entity.AuxIndex;//獲取sql語句SqlDataAdapter AuxTSda = new SqlDataAdapter(AuxTSql, conn);?? //(查詢語句和連接工具)AuxTSda.Fill(auxTDs);??? //將適配器數據存入DataSet工具中//autxRecords = new List<AuxRecord>();AuxRecord aux = null;foreach (DataRow auxrow in auxTDs.Tables[0].Rows){aux = new AuxRecord();aux.DataPoint = DataProcessor.RowValue(auxrow, "Data_Point", 0);aux.IvIndex = DataProcessor.RowValue(auxrow, "IvIndex", 0);foreach (DataColumn col in auxTDs.Tables[0].Columns){if (col.ColumnName.StartsWith("T") || col.ColumnName.StartsWith("V")){aux.Data.Add(DataProcessor.RowValue(row, col.ColumnName, 0D));}}autxRecords.Add(aux);}autxRecordsList.Add(autxRecords);Console.WriteLine("根據記錄數據查詢輔助通道溫度數據成功");}//conn.Close();//開始向數據庫插入中傳遞參數bool isStoreSuccess = StoreRecordData(idxList[i],recordList,autxRecordsList);if (isStoreSuccess){Console.WriteLine("存入數據庫成功");}else{Console.WriteLine("存入數據庫失敗");}//開始休眠Console.WriteLine("開始休眠...");System.Threading.Thread.Sleep(1000 * 5);//Console.WriteLine("休眠結束...");}//Console.WriteLine("查詢輔助通道溫度數據成功");//Console.ReadKey();}}public static bool StoreRecordData(IdxRecord idx, List<Record> recordList, List<List<AuxRecord>> autxRecordsList){//存入bak數據庫string constrBak = "server=localhost;database=BadaoBak;uid=sa;pwd=123";using (SqlConnection conn = new SqlConnection(constrBak))//constr：數據庫連接配置{conn.Open();//開啟事務SqlTransaction trans = conn.BeginTransaction();SqlCommand cmd = new SqlCommand();cmd.Connection = conn;//添加連接工具cmd.Transaction = trans;//添加事務try{cmd.CommandText = "INSERT INTO idx1_1 values? ('" + idx.IdxID + "','" + idx.DataPoint + "','" + idx.StepEnd +"')";//添加sql語句cmd.ExecuteNonQuery();//執行Console.WriteLine("插入索引數據成功");foreach(Record record in recordList){cmd.CommandText = "INSERT INTO WsC1_1 values? ('" + record.DataPoint + "','" + record.ScheduleIndex + "','" + record.AuxIndex + "')";//添加sql語句cmd.ExecuteNonQuery();//執行}Console.WriteLine("插入記錄數據成功");foreach (List<AuxRecord> auxRecords in autxRecordsList){cmd.CommandText = "INSERT INTO Aux1_1_25 values? ('" + auxRecords[0].DataPoint + "','" + auxRecords[0].IvIndex + "','" + auxRecords[0].Data[0] + "')";//添加sql語句cmd.ExecuteNonQuery();//執行}Console.WriteLine("插入輔助通道溫度數據成功");trans.Commit();//執行完成之后提交return true;}catch (Exception e){//執行sql語句失敗，事務回滾trans.Rollback();return false;}finally{conn.Close();}}}

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