using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Data;using System.Data.SqlClient;namespace 模拟ATM机转账{    static class DBHelp    {        public static bool IDUBySql(string sql)        {            bool fa = false;            string str = "server=.;integrated security=true;database=BankDB";            SqlConnection sqlconn = new SqlConnection(str);            SqlCommand sqlcomm = new SqlCommand(sql, sqlconn);            try            {                sqlconn.Open();                //开启事务                sqlcomm.Transaction = sqlconn.BeginTransaction();                fa = sqlcomm.ExecuteNonQuery() > 0 ? true : false;                //提交事务                sqlcomm.Transaction.Commit();            }            catch (SqlException ex)            {                //回滚事务                sqlcomm.Transaction.Rollback();            }            finally            {                sqlconn.Close();            }            return fa;        }        public static DataTable GetTableBySql(string sql)        {            DataTable ta = new DataTable();            string str = "server=.;integrated security=true;database=BankDB";            SqlConnection sqlconn = new SqlConnection(str);            SqlCommand sqlcomm = new SqlCommand(sql, sqlconn);            SqlDataAdapter da = new SqlDataAdapter(sqlcomm);            da.Fill(ta);            return ta;        }    }}

--G．事务：--定义转账事务，并实现转账操作进行测试，注意：转账过程中实际上两个交易过程，一个是“存入”，一个是“支取”，注意添加交易记录到交易信息表中begin tran tran_bankdeclare @cou intset @cou=0update cardInfo set balance=balance-900 where cardID=‘1010 3576 1234 5678‘update cardInfo set balance=balance+500 where cardID=‘1010 3576 1212 1134‘set @cou=@@error+@couif(@cou<>0)    begin        rollback tran --滚回    endelse    begin        commit tran        insert into transInfo(cardID,transType ,transMoney,remark) values (‘1010 3576 1212 1134‘,‘存入‘,500,‘李四存款500‘)        insert into transInfo(cardID,transType ,transMoney,remark) values (‘1010 3576 1234 5678‘,‘支取‘,900,‘张三取款900‘)        print ‘交易成功，以保存新数据‘    endgo