Microsoft.Practices.EnterpriseLibrary.Data 使用笔记

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