vb.net 数据库访问操作

Imports System.Data

Imports System.Data.SqlClient

Namespace DA

    Public Class DBConnector

        Dim _connectionString As String

        Dim _DBConnection As System.Data.SqlClient.SqlConnection

        Public Sub New(ByVal connectionString As String)

            _connectionString = connectionString

        End Sub

        Property DBConnection() As IDbConnection

            Get

                Return _DBConnection

            End Get

            Set(ByVal value As IDbConnection)

                _DBConnection = value

            End Set

        End Property

        Public Sub GetDBConnection()

            Try

                If _DBConnection Is Nothing Then

                    _DBConnection = New System.Data.SqlClient.SqlConnection(_connectionString)

                End If

            Catch ex As Exception

                Throw ex

            End Try

          

        End Sub

        Public Sub OpenDBConnection()

            Try

                If _DBConnection Is Nothing Then

                    GetDBConnection()

                End If

                If _DBConnection.State <> ConnectionState.Open Then

                    _DBConnection.Open()

                End If

            Catch ex As Exception

                _DBConnection.Close()

                Throw ex

            End Try

        End Sub

        Public Sub CloseDBConnection()

            Try

                If Not _DBConnection Is Nothing Then

                    If _DBConnection.State = ConnectionState.Open Then

                        _DBConnection.Close()

                    End If

                End If

            Catch ex As Exception

            End Try

        End Sub

    End Class

End Namespace

 

Imports Gates.DA

Imports System.Data

Imports System.Data.SqlClient

Namespace DA

    Public Class DBTransaction

        Dim _DBConnector As DBConnector

        Dim _DBTransaction As IDbTransaction

        Dim _TimeOut As Integer = 0

        Dim _isTransaction As Boolean = False

        Public Sub New(ByVal connectionString As String)

            _DBConnector = New DBConnector(connectionString)

        End Sub

        Public Property DBTransaction() As IDbTransaction

            Get

                Return _DBTransaction

            End Get

            Set(ByVal value As IDbTransaction)

                _DBTransaction = value

            End Set

        End Property

        Public Sub BeginTransactio()

            Try

                If _DBConnector Is Nothing Then

                    _DBConnector.GetDBConnection()

                End If

                If _DBConnector.DBConnector.State = ConnectionState.Open Then

                    _DBConnector.OpenDBConnection()

                End If

                _DBTransaction = _DBConnector.DBConnector.BeginTransaction(IsolationLevel.ReadUncommitted)

                _isTransaction = True

            Catch ex As Exception

                _DBConnector.CloseDBConnection()

                _isTransaction = False

            End Try

        End Sub

        Public Sub CommitTransaction()

            Try

                _DBTransaction.Commit()

            Catch ex As Exception

            Finally

                _DBTransaction.Dispose()

                _DBConnector.CloseDBConnection()

                _isTransaction = False

            End Try

        End Sub

        Public Sub RollbackTransaction()

            Try

                If Not _DBTransaction Is Nothing Then

                    _DBTransaction.Rollback()

                    _DBTransaction.Dispose()

                End If

                _DBConnector.CloseDBConnection()

                _isTransaction = False

            Catch ex As Exception

            End Try

        End Sub

        Private Function getCommandTrans(ByVal commandText As String, Optional ByVal isSP As Boolean = False) As IDbCommand

            Dim selCommand As New System.Data.SqlClient.SqlCommand

            Try

                _DBConnector.OpenDBConnection()

                selCommand.Connection = _DBConnector.DBConnector

                If isSP Then

                    selCommand.CommandType = CommandType.StoredProcedure

                Else

                    selCommand.CommandType = CommandType.Text

                End If

                selCommand.CommandText = commandText

                If _TimeOut > 0 Then

                    selCommand.CommandTimeout = _TimeOut

                End If

                If _isTransaction Then

                    selCommand.Transaction = _DBTransaction

                End If

                Return selCommand

 

            Catch ex As Exception

                RollbackTransaction()

                Throw ex

            End Try

        End Function

        Private Function getAdapterTrans(ByVal command As IDbCommand) As IDbDataAdapter

            Try

                Return New System.Data.SqlClient.SqlDataAdapter(command)

            Catch ex As Exception

                Throw ex

            End Try

        End Function

        Public Function SQLToDataset(ByVal tableName As String, ByVal strSQL As String) As DataSet

            Dim reDS As New DataSet

            Dim selCommand As IDbCommand

            Dim selAdpatee As IDataAdapter

            Try

                Dim tables() As String

                tables = tableName.Split("|")

                selCommand = getCommandTrans(strSQL)

                selAdpatee = getAdapterTrans(selCommand)

                selAdpatee.Fill(reDS)

                For i As Integer = 0 To tables.Count - 1

                    reDS.Tables(i).TableName = tables(0)

                Next

                Return reDS

            Catch ex As Exception

                Throw ex

            End Try

        End Function

        Public Function ExecSQL(ByVal strSql As String) As Boolean

            Dim selCommand As IDbCommand

            Try

                selCommand = getCommandTrans(strSql)

                selCommand.ExecuteNonQuery()

                Return True

            Catch ex As Exception

                Return False

                Throw

            End Try

        End Function

 

    End Class

End Namespace