Data Access Application Block QuickStart 的详细使用过程
Data Access Application Block QuickStart 的详细使用过程
首先是建立数据库。这是我的sql脚本。
use
master
go
create
database
DataAccessTest
go
use
DataAccessTest
go
create
table
[
Students
]
--
学生
(
[
SerialNumber
]
int
identity
(
1
,
1
)
primary
key
,
--
唯一标识
[
SID
]
nvarchar
(
50
),
--
学号
[
SName
]
nvarchar
(
50
) ,
--
姓名
[
SClass
]
nvarchar
(
50
)
--
班级
)
go
insert
into
[
Students
]
(
[
SID
]
,
[
SName
]
,
[
SClass
]
)
values
(
'
06130001
'
,
'
Jim Carry
'
,
'
CET Band 4
'
)
insert
into
[
Students
]
(
[
SID
]
,
[
SName
]
,
[
SClass
]
)
values
(
'
06130002
'
,
'
龌龊男
'
,
'
CET Band 4
'
)
insert
into
[
Students
]
(
[
SID
]
,
[
SName
]
,
[
SClass
]
)
values
(
'
06130003
'
,
'
dudu
'
,
'
CET Band 4
'
)
insert
into
[
Students
]
(
[
SID
]
,
[
SName
]
,
[
SClass
]
)
values
(
'
06130004
'
,
'
猥琐男
'
,
'
CET Band 6
'
)
insert
into
[
Students
]
(
[
SID
]
,
[
SName
]
,
[
SClass
]
)
values
(
'
06130005
'
,
'
章朝阳
'
,
'
CET Band 6
'
)
go
create
procedure
[
GetStudentsByClass
]
(
@SClass
nvarchar
(
50
))
as
select
*
from
[
Students
]
where
[
SClass
]
=
@SClass
go
create
procedure
[
AddStudent
]
(
@SID
nvarchar
(
50
),
@SName
nvarchar
(
50
),
@SClass
nvarchar
(
50
))
as
insert
into
[
Students
]
(
[
SID
]
,
[
SName
]
,
[
SClass
]
)
values
(
@SID
,
@SName
,
@SClass
)
select
*
from
[
Students
]
where
[
SerialNumber
]
=
SCOPE_IDENTITY
()
go
create
procedure
[
DeleteStudent
]
(
@SerialNumber
int
)
as
delete
from
[
Students
]
where
[
SerialNumber
]
=
@SerialNumber
go
create
procedure
[
UpdateStudent
]
(
@SerialNumber
int
,
@SID
nvarchar
(
50
),
@SName
nvarchar
(
50
),
@SClass
nvarchar
(
50
))
as
update
[
Students
]
set
[
SID
]
=
@SID
,
[
SName
]
=
@SName
,
[
SClass
]
=
@SClass
where
[
SerialNumber
]
=
@SerialNumber
select
*
from
[
Students
]
where
[
SerialNumber
]
=
@SerialNumber
go
create
procedure
[
GetStudent
]
(
@SerialNumber
int
,
@SID
nvarchar
(
50
) output,
@SName
nvarchar
(
50
) output,
@SClass
nvarchar
(
50
) output)
as
select
@SID
=
[
SID
]
,
@SName
=
[
SName
]
,
@SClass
=
[
SClass
]
from
[
Students
]
where
[
SerialNumber
]
=
@SerialNumber
go
create
procedure
[
GetStudentName
]
(
@SerialNumber
int
)
as
select
[
SName
]
from
[
Students
]
where
[
SerialNumber
]
=
@SerialNumber
go
这里使用的是sql server 2005 express edition。这里有一个东西需要注意一下：在UpdateStudent存储过程中在update语句执行完成之后又紧跟了一句select语句，在微软提供的源代码中对这种行为有一行注释：This statement is used to update the DataSet if changes are done on the updated record (identities, timestamps or triggers )。好像是说这条语句是来在被更新的数据又被更新之后来更新DataSet的，呵呵，好多更新，没太明白，请高人指点一下嘻嘻。
建立了数据库之后，为了简单，我建立了一个console application。然后在项目中添加了一个app.config文件。这还是我第一次使用app.config呢！以前一直都是做web开发的嘻嘻。文件如下：
<?
xml version="1.0" encoding="utf-8"
?>
<
configuration
>
<
configSections
>
<
section
name
="dataConfiguration"
type
="Microsoft.Practices.EnterpriseLibrary.Data.Configuration.DatabaseSettings, Microsoft.Practices.EnterpriseLibrary.Data"
/>
</
configSections
>
<
connectionStrings
>
<
add
name
="DataAccessTest"
providerName
="System.Data.SqlClient"
connectionString
="server=.\sqlexpress;database=DataAccessTest;Integrated Security=true"
/>
</
connectionStrings
>
<
dataConfiguration
defaultDatabase
="DataAccessTest"
/>
</
configuration
>
在这里首先注册了一个配置段，对应于DatabaseSettings类型。就是说配置文件下面的dataConfiguration部分要用DatabaseSettings类来处理，至于怎么处理，不知道。希望在分析了源代码之后能够了解。接下来dataConfiguration的defaultDatabase属性的内容如果我没猜错的话应该是上面的connectionString，就是说默认的数据库是通过ConnectionString来指定的。在后面声明数据库的时候也可以指定数据库名，这里猜测可能就是ConnectionString，不过我没有测试。
在创建了app.config之后要添加引用。在我的项目中使用Data Access Application Block的时候要添加两个引用：Microsoft.Practices.EnterpriseLibrary.Common.dll和Microsoft.Practices.EnterpriseLibrary.Data.dll，至于其它时候是不是需要添加别的引用，还是不知道。这两个文件可以在安装Microsoft Enterprise Library January 2006路径的bin文件夹中找到。
接下来开始正式写代码了。在微软的样例中一共提供了六种应用情况，但是后两种应用（事务支持和利用sql server返回xml，只能应用于sql server）我从来都没有使用过，所以就没有实现。感兴趣的话可以自己看看嘻嘻。
第一个函数是使用DataReader直接返回数据的例子，也是我平时最长使用的方法。代码如下：
static
void
PrintAllStudents()
{
Database db = DatabaseFactory.CreateDatabase(); DbCommand dbCommand = db.GetSqlStringCommand("select * from Students"); using (IDataReader reader = db.ExecuteReader(dbCommand))
{
while (reader.Read()) { Console.WriteLine("SN:{0} ID:{1} Name:{2}\t Class:{3}", reader[0], reader[1], reader[2], reader[3]);
} }
}
这里使用了工厂模式生成数据库对象，还使用了全新的DbXXX对象。这些东西都是我很感兴趣的，不过因为开窍时间比较晚，暂时对他们还没有什么认识，希望以后能好好研究一下。另外我在前面说可以在创建数据库的时候指定ConnectionString，就是指在DatabaseFactory.CreateDatabase()时可以传递一个string类型的参数，估计就是你所想指定的ConnectionString。剩下的部分没有什么差别了，只不过使用的方法和ado.net不是很一样。
接下来是使用存储过程的例子：
static
void
GetCETBand4Students()
{ Database db = DatabaseFactory.CreateDatabase(); DbCommand dbCommand = db.GetStoredProcCommand("GetStudentsByClass"); db.AddInParameter(dbCommand, "SClass", DbType.String, "CET Band 4"); DataSet band4Students = db.ExecuteDataSet(dbCommand); foreach (DataRow row in band4Students.Tables[0].Rows) { Console.WriteLine("SN:{0} ID:{1} Name:{2}\t Class:{3}", row[0], row[1], row[2], row[3]); }}
这里通过AddInParameter方法向指定的DbCommand对象加入参数。接下来的代码就没有什么值得说的部分了，一起贴出来。
using
System;
using
System.Collections.Generic;
using
System.Text;
using
Microsoft.Practices.EnterpriseLibrary.Data;
using
System.Data.Common;
using
System.Data;
namespace
DataAccessTest
{ class Program { static void Main(string[] args) { Console.Write("Press \"enter\" to run IDataReader & direct sql string demo:"); Console.ReadLine(); Console.WriteLine(); PrintAllStudents(); Console.WriteLine(); Console.Write("Press \"enter\" to run DataSet & stored procedure demo:"); Console.ReadLine(); Console.WriteLine(); GetCETBand4Students(); Console.WriteLine(); Console.Write("Press \"enter\" to run updating with DataSet demo:"); Console.ReadLine(); Console.WriteLine(); UpdateWithDataSet(); Console.WriteLine(); Console.Write("Press \"enter\" to run output parameter demo:"); Console.ReadLine(); Console.WriteLine(); OutputParameter(); Console.WriteLine(); Console.Write("Press \"enter\" to run ExecuteScalar demo:"); Console.ReadLine(); Console.WriteLine(); ExecuteScalar(); Console.WriteLine(); Console.WriteLine("All demos finished, press\"enter\" to exit."); Console.ReadLine(); }static void PrintAllStudents(){ Database db = DatabaseFactory.CreateDatabase(); DbCommand dbCommand = db.GetSqlStringCommand("select * from Students"); using (IDataReader reader = db.ExecuteReader(dbCommand)) { while (reader.Read()) { Console.WriteLine("SN:{0} ID:{1} Name:{2}\t Class:{3}", reader[0], reader[1], reader[2], reader[3]); } }} static void GetCETBand4Students() { Database db = DatabaseFactory.CreateDatabase(); DbCommand dbCommand = db.GetStoredProcCommand("GetStudentsByClass"); db.AddInParameter(dbCommand, "SClass", DbType.String, "CET Band 4"); DataSet band4Students = db.ExecuteDataSet(dbCommand); foreach (DataRow row in band4Students.Tables[0].Rows) { Console.WriteLine("SN:{0} ID:{1} Name:{2}\t Class:{3}", row[0], row[1], row[2], row[3]); } } static void UpdateWithDataSet() { Database db = DatabaseFactory.CreateDatabase(); DbCommand dbCommand = db.GetSqlStringCommand("select * from Students"); DataSet students = new DataSet(); db.LoadDataSet(dbCommand, students, "Students"); students.Tables[0].Rows.Add(new object[] { DBNull.Value, "06130006", "tel1sen", "CET Band 2" }); students.Tables[0].Rows[0]["SClass"] = "CET Band 8"; DbCommand insertCommand = db.GetStoredProcCommand("AddStudent"); db.AddInParameter(insertCommand, "SID", DbType.String, "SID", DataRowVersion.Current); db.AddInParameter(insertCommand, "SName", DbType.String, "SName", DataRowVersion.Current); db.AddInParameter(insertCommand, "SClass", DbType.String, "SClass", DataRowVersion.Current); DbCommand deleteCommand = db.GetStoredProcCommand("DeleteStudent"); db.AddInParameter(deleteCommand, "SerialNumber", DbType.Int32, "SerialNumber", DataRowVersion.Current); DbCommand updateCommand = db.GetStoredProcCommand("UpdateStudent"); db.AddInParameter(updateCommand, "SerialNumber", DbType.Int32, "SerialNumber", DataRowVersion.Current); db.AddInParameter(updateCommand, "SID", DbType.String, "SID", DataRowVersion.Current); db.AddInParameter(updateCommand, "SName", DbType.String, "SName", DataRowVersion.Current); db.AddInParameter(updateCommand, "SClass", DbType.String, "SClass", DataRowVersion.Current); Console.WriteLine("Rows affected:{0}", db.UpdateDataSet(students, "Students", insertCommand, updateCommand, deleteCommand, UpdateBehavior.Standard)); PrintAllStudents(); } static void OutputParameter() { Database db = DatabaseFactory.CreateDatabase(); DbCommand dbCommand = db.GetStoredProcCommand("GetStudent"); db.AddInParameter(dbCommand, "SerialNumber", DbType.Int32, 1); db.AddOutParameter(dbCommand, "SID", DbType.String, 50); db.AddOutParameter(dbCommand, "SName", DbType.String, 50); db.AddOutParameter(dbCommand, "SClass", DbType.String, 50); db.ExecuteNonQuery(dbCommand); Console.WriteLine("SN:{0} ID:{1} Name:{2}\t Class:{3}", db.GetParameterValue(dbCommand, "SerialNumber"), db.GetParameterValue(dbCommand, "SID"), db.GetParameterValue(dbCommand, "SName"), db.GetParameterValue(dbCommand, "SClass")); } private static void ExecuteScalar() { Database db = DatabaseFactory.CreateDatabase(); DbCommand dbCommand = db.GetStoredProcCommand("GetStudentName", 1); Console.WriteLine("Name:{0}", db.ExecuteScalar(dbCommand)); } }}
当然这只是Data Access Application Block的一个极其简单的应用，而且Data Access Application Block的使用方法远不止于此
这篇文章是从博客园：骑士的荣誉 看到的，虽然简单，确实入门兄弟的上等参考，顾贴一下