封装数据库操作，并且提供事务处理。
复制代码 代码如下:
使用DbProviderFactories的数据库操作类
Imports System.Data
Imports System.Configuration
Imports System.Data.Common
'*******************************************************************
'* Page/Class Name：XPDBHelper.vb
'* Title：使用DbProviderFactories的数据库操作类
'* Description：简单三层结构数据库操作类
'* Copyright：
'* Company：
'* @author：Owen,Yuan
'* Create Date：2010/3/9 14:04:56
'* Last Modifier：
'* Last Modify Date：
'*******************************************************************
Public Class XPDBHelper
'取得连接字符串中的数据库驱动提供者
Private Shared dbProviderName As String = ConfigurationManager.ConnectionStrings("ConnectionString").ProviderName
'取得数据库连接字符串
Private Shared dbConnectionString As String = ConfigurationManager.ConnectionStrings("ConnectionString").ConnectionString
'数据库连接。
Private connection As DbConnection
Public Sub New()
Me.connection = CreateConnection(XPDBHelper.dbConnectionString)
End Sub
Public Sub New(ByVal connectionString As String)
Me.connection = CreateConnection(connectionString)
End Sub
'创建数据库连接
Public Shared Function CreateConnection() As DbConnection
Dim dbfactory As DbProviderFactory = DbProviderFactories.GetFactory(dbProviderName)
Dim dbconn As DbConnection = dbfactory.CreateConnection()
dbconn.ConnectionString = XPDBHelper.dbConnectionString
Return dbconn
End Function
'创建数据库连接
Public Shared Function CreateConnection(ByVal connectionString As String) As DbConnection
Dim dbfactory As DbProviderFactory = DbProviderFactories.GetFactory(dbProviderName)
Dim dbconn As DbConnection = dbfactory.CreateConnection()
dbconn.ConnectionString = connectionString
Return dbconn
End Function
'根据存储过程创建DbCommand
Public Function GetStoredProcCommond(ByVal storedProcedure As String) As DbCommand
Dim dbCommand As DbCommand = connection.CreateCommand()
dbCommand.CommandText = storedProcedure
dbCommand.CommandType = CommandType.StoredProcedure
Return dbCommand
End Function
'根据SQL语句创建DbCommand
Public Function GetSqlStringCommond(ByVal sqlQuery As String) As DbCommand
Dim dbCommand As DbCommand = connection.CreateCommand()
dbCommand.CommandText = sqlQuery
dbCommand.CommandType = CommandType.Text
Return dbCommand
End Function
#Region "增加参数"
Public Sub AddParameterCollection(ByVal cmd As DbCommand, ByVal dbParameterCollection As DbParameterCollection)
For Each dbParameter As DbParameter In dbParameterCollection
cmd.Parameters.Add(dbParameter)
Next
End Sub
Public Sub AddOutParameter(ByVal cmd As DbCommand, ByVal parameterName As String, ByVal dbType As DbType, ByVal size As Integer)
Dim dbParameter As DbParameter = cmd.CreateParameter()
dbParameter.DbType = dbType
dbParameter.ParameterName = parameterName
dbParameter.Size = size
dbParameter.Direction = ParameterDirection.Output
cmd.Parameters.Add(dbParameter)
End Sub
Public Sub AddInParameter(ByVal cmd As DbCommand, ByVal parameterName As String, ByVal dbType As DbType, ByVal value As Object)
Dim dbParameter As DbParameter = cmd.CreateParameter()
dbParameter.DbType = dbType
dbParameter.ParameterName = parameterName
dbParameter.Value = value
dbParameter.Direction = ParameterDirection.Input
cmd.Parameters.Add(dbParameter)
End Sub
Public Sub AddReturnParameter(ByVal cmd As DbCommand, ByVal parameterName As String, ByVal dbType As DbType)
Dim dbParameter As DbParameter = cmd.CreateParameter()
dbParameter.DbType = dbType
dbParameter.ParameterName = parameterName
dbParameter.Direction = ParameterDirection.ReturnValue
cmd.Parameters.Add(dbParameter)
End Sub
Public Function GetParameter(ByVal cmd As DbCommand, ByVal parameterName As String) As DbParameter
Return cmd.Parameters(parameterName)
End Function
#End Region
#Region "执行"
'执行DbCommand，返回DataSet
Public Function ExecuteDataSet(ByVal cmd As DbCommand) As DataSet
Dim dbfactory As DbProviderFactory = DbProviderFactories.GetFactory(dbProviderName)
Dim dbDataAdapter As DbDataAdapter = dbfactory.CreateDataAdapter()
dbDataAdapter.SelectCommand = cmd
Dim ds As DataSet = New DataSet()
dbDataAdapter.Fill(ds)
Return ds
End Function
'执行DbCommand，返回DataTable
Public Function ExecuteDataTable(ByVal cmd As DbCommand) As DataTable
Dim dbfactory As DbProviderFactory = DbProviderFactories.GetFactory(dbProviderName)
Dim dbDataAdapter As DbDataAdapter = dbfactory.CreateDataAdapter()
dbDataAdapter.SelectCommand = cmd
Dim dataTable As DataTable = New DataTable()
dbDataAdapter.Fill(dataTable)
Return dataTable
End Function
'执行DbCommand，返回DbDataReader
Public Function ExecuteReader(ByVal cmd As DbCommand) As DbDataReader
cmd.Connection.Open()
Dim reader As DbDataReader = cmd.ExecuteReader(CommandBehavior.CloseConnection)
cmd.Connection.Close()
Return reader
End Function
Public Function ExecuteNonQuery(ByVal cmd As DbCommand) As Integer
cmd.Connection.Open()
Dim ret As Integer = cmd.ExecuteNonQuery()
cmd.Connection.Close()
Return ret
End Function
Public Function ExecuteScalar(ByVal cmd As DbCommand) As Object
cmd.Connection.Open()
Dim ret As Object = cmd.ExecuteScalar()
cmd.Connection.Close()
Return ret
End Function
#End Region
#Region "执行事务"
Public Function ExecuteDataSet(ByVal cmd As DbCommand, ByVal t As XPTransaction) As DataSet
cmd.Connection = t.DbConnection
cmd.Transaction = t.DbTransact
Dim dbfactory As DbProviderFactory = DbProviderFactories.GetFactory(XPDBHelper.dbProviderName)
Dim dbDataAdapter As DbDataAdapter = dbfactory.CreateDataAdapter()
dbDataAdapter.SelectCommand = cmd
Dim ds As DataSet = New DataSet()
dbDataAdapter.Fill(ds)
Return ds
End Function
Public Function ExecuteDataTable(ByVal cmd As DbCommand, ByVal t As XPTransaction) As DataTable
cmd.Connection = t.DbConnection
cmd.Transaction = t.DbTransact
Dim dbfactory As DbProviderFactory = DbProviderFactories.GetFactory(XPDBHelper.dbProviderName)
Dim dbDataAdapter As DbDataAdapter = dbfactory.CreateDataAdapter()
dbDataAdapter.SelectCommand = cmd
Dim dataTable As DataTable = New DataTable()
dbDataAdapter.Fill(dataTable)
Return dataTable
End Function
Public Function ExecuteReader(ByVal cmd As DbCommand, ByVal t As XPTransaction) As DbDataReader
cmd.Connection.Close()
cmd.Connection = t.DbConnection
cmd.Transaction = t.DbTransact
Dim reader As DbDataReader = cmd.ExecuteReader()
Return reader
End Function
Public Function ExecuteNonQuery(ByVal cmd As DbCommand, ByVal t As XPTransaction) As Integer
cmd.Connection.Close()
cmd.Connection = t.DbConnection
cmd.Transaction = t.DbTransact
Return cmd.ExecuteNonQuery()
End Function
Public Function ExecuteScalar(ByVal cmd As DbCommand, ByVal t As XPTransaction) As Object
cmd.Connection.Close()
cmd.Connection = t.DbConnection
cmd.Transaction = t.DbTransact
Return cmd.ExecuteScalar()
End Function
#End Region
End Class
简单三层结构数据库事务处理类
复制代码 代码如下: