微软企业库数据访问

Database db = null;


#region 一般调用 
db = DatabaseFactory.CreateDatabase("Connection String"); 
int count = (int)db.ExecuteScalar(CommandType.Text, "SELECT Count(*) From cms_company"); 
string message = string.Format("There are {0} customers in the database", count.ToString()); 
Response.Write(message); 
#endregion 


#region 带返回参数，返回值和返回数据集，一般参数的存储过程 
//CREATE PROCEDURE [dbo].[kword] 
//@kword varchar(250)='', 
//@top int, 
//@otop varchar(250) output 
//As 
//select top 10 * from Table1 where ntitle like '%'+@kword+'%' and id>@top 
//declare @flag int 
//select @flag=100 
//SET @otop='返回值' 
//return @flag 
db = DatabaseFactory.CreateDatabase("serverConnectionString");//连接字符串变量名 
DbCommand dbcomm = db.GetStoredProcCommand("kword");//存储过程名 
db.AddInParameter(dbcomm, "@kword", DbType.String, "创业");//参数名 类型 值 
db.AddInParameter(dbcomm, "top", DbType.Int32, 2);//参数名 类型 值 
db.AddOutParameter(dbcomm, "otop", DbType.String, 250);//output参数名 类型 长度 
//关键在这里，添加一个参数@RETURN_VALUE 类型为ReturnValue 
db.AddParameter(dbcomm, "@RETURN_VALUE", DbType.String, ParameterDirection.ReturnValue, "", DataRowVersion.Current, null); 
DataSet ds = db.ExecuteDataSet(dbcomm);//必须有执行的动作后面才能获取值 
//title = (string)db.ExecuteScalar(dbcomm);如果返回只有一个数据，这样也是可以的 
GridView1.DataSource = ds; 
GridView1.DataBind(); 

Response.Write("<br>output输出参数值：" + db.GetParameterValue(dbcomm, "otop").ToString()); 
// int testvalue = (int)dbcomm.Parameters["@RETURN_VALUE"].Value; //另一种获取值的方式 
Response.Write("<br />return返回参数值：" + db.GetParameterValue(dbcomm, "RETURN_VALUE").ToString()); 
#endregion 



#region 使用事务记录操作数据库 
//CREATE TABLE [dbo].[Table1]( 
// [id] [int] IDENTITY(1,1) NOT NULL, 
// [ntitle] [varchar](250) NOT NULL, 
// [valuea] [varchar](250) NULL, 
// CONSTRAINT [PK_Table1] PRIMARY KEY CLUSTERED 
//( 
// [ntitle] ASC 
//)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] 
//) ON [PRIMARY] 
db = DatabaseFactory.CreateDatabase("serverConnectionString"); 
using (IDbConnection conn = db.CreateConnection()) 
{ 
conn.Open(); 
IDbTransaction _trans = conn.BeginTransaction(); 
try 
{ 
DbCommand _cmd = db.GetSqlStringCommand("INSERT INTO [Table1]([ntitle],[valuea]) VALUES(@ntitle,@valuea)"); 
db.AddInParameter(_cmd, "ntitle", DbType.String, "AA"); 
db.AddInParameter(_cmd, "valuea", DbType.String, "AA"); 
db.ExecuteNonQuery(_cmd, _trans as DbTransaction); 
db.ExecuteNonQuery(_cmd, _trans as DbTransaction);//ntitle字段上建有唯一索引，故第二次插入同样记录时会报错 
_trans.Commit(); 
} 
catch 
{ 
try 
{ 
_trans.Rollback();//事务提交失败时，则回滚(是否回滚成功，可查看表中有无AA的记录即可) 
} 
catch { } 
} 
finally 
{ 
conn.Close(); 
} 
} 
#endregion