VB.net版本的数据库访问类DataBaseAccess

在开发一个VB.net的项目时,曾经整理出了一个DataBaseAccess的访问类,现在将该类分享下:

Imports System

Imports System.IO

Imports System.Text

Imports System.Data

Imports System.Data.SqlClient

Namespace SqlDataProvider

Public Class DataBaseAccess

#Region "Local Property Declaration"

Dim _connectionString As String

#End Region

#Region " Constructor "

''' <summary>

''' Initializes a new instance of the ADO.SqlDatabase class.

''' </summary>

''' <param name="connectionString">The connection used to open the SQL Server database.</param>

Public Sub New(ByVal connectionString As String)

_connectionString = connectionString

End Sub

#End Region

#Region " Public Properties "

''' <summary>

''' Gets or sets the string used to open a SQL Server database.

''' </summary>

''' <returns>The connection string that includes the source database name, and other parameters needed to establish the initial connection.</returns>

Public Property ConnectionString() As String

Get

Return _connectionString

End Get

Set(ByVal value As String)

_connectionString = value

End Set

End Property

#End Region

#Region " Private Methods "

Private Sub AssignParameters(ByVal cmd As SqlCommand, ByVal cmdParameters() As SqlParameter)

If (cmdParameters Is Nothing) Then Exit Sub

For Each p As SqlParameter In cmdParameters

cmd.Parameters.Add(p)

Next

End Sub

Private Sub AssignParameters(ByVal cmd As SqlCommand, ByVal parameterValues() As Object)

If Not (cmd.Parameters.Count - 1 = parameterValues.Length) Then Throw New ApplicationException("Stored procedure's parameters and parameter values does not match.")

Dim i As Integer

For Each param As SqlParameter In cmd.Parameters

If Not (param.Direction = ParameterDirection.Output) AndAlso Not (param.Direction = ParameterDirection.ReturnValue) Then

param.Value = parameterValues(i)

i += 1

End If

Next

End Sub

#End Region

#Region " ExecuteNonQuery "

''' <summary>

''' Executes a Transact-SQL statement against the connection and returns the number of rows affected.

''' </summary>

''' <param name="cmd">The Transact-SQL statement or stored procedure to execute at the data source.</param>

''' <param name="cmdType">A value indicating how the System.Data.SqlClient.SqlCommand.CommandText property is to be interpreted.</param>

''' <param name="parameters">The parameters of the Transact-SQL statement or stored procedure.</param>

''' <returns>The number of rows affected.</returns>

Public Function ExecuteNonQuery(ByVal cmd As String, ByVal cmdType As CommandType, Optional ByVal parameters() As SqlParameter = Nothing) As Integer

Dim connection As SqlConnection = Nothing

Dim transaction As SqlTransaction = Nothing

Dim command As SqlCommand = Nothing

Dim res As Integer = -1

Try

connection = New SqlConnection(_connectionString)

command = New SqlCommand(cmd, connection)

command.CommandType = cmdType

Me.AssignParameters(command, parameters)

connection.Open()

transaction = connection.BeginTransaction()

command.Transaction = transaction

res = command.ExecuteNonQuery()

transaction.Commit()

Catch ex As Exception

If Not (transaction Is Nothing) Then

transaction.Rollback()

End If

Throw New Exception(ex.Message, ex.InnerException)

Finally

If Not (connection Is Nothing) AndAlso (connection.State = ConnectionState.Open) Then connection.Close()

If Not (command Is Nothing) Then command.Dispose()

If Not (transaction Is Nothing) Then transaction.Dispose()

End Try

Return res

End Function

''' <summary>

''' Executes a Transact-SQL statement against the connection and returns the number of rows affected.

''' </summary>

''' <param name="spname">The stored procedure to execute at the data source.</param>

''' <param name="returnValue">The returned value from stored procedure.</param>

''' <param name="parameterValues">The parameter values of the stored procedure.</param>

''' <returns>The number of rows affected.</returns>

Public Function ExecuteNonQuery(ByVal spname As String, ByRef returnValue As Integer, ByVal ParamArray parameterValues() As Object) As Integer

Dim connection As SqlConnection = Nothing

Dim transaction As SqlTransaction = Nothing

Dim command As SqlCommand = Nothing

Dim res As Integer = -1

Try

connection = New SqlConnection(_connectionString)

command = New SqlCommand(spname, connection)

command.CommandType = CommandType.StoredProcedure

connection.Open()

SqlCommandBuilder.DeriveParameters(command)

Me.AssignParameters(command, parameterValues)

transaction = connection.BeginTransaction()

command.Transaction = transaction

res = command.ExecuteNonQuery()

returnValue = command.Parameters(0).Value

transaction.Commit()

Catch ex As Exception

If Not (transaction Is Nothing) Then

transaction.Rollback()

End If

Throw New Exception(ex.Message, ex.InnerException)

Finally

If Not (connection Is Nothing) AndAlso (connection.State = ConnectionState.Open) Then connection.Close()

If Not (command Is Nothing) Then command.Dispose()

If Not (transaction Is Nothing) Then transaction.Dispose()

End Try

Return res

End Function

#End Region

#Region " ExecuteScalar "

''' <summary>

''' Executes the query, and returns the first column of the first row in the result set returned by the query. Additional columns or rows are ignored.

''' </summary>

''' <param name="cmd">The Transact-SQL statement or stored procedure to execute at the data source.</param>

''' <param name="cmdType">A value indicating how the System.Data.SqlClient.SqlCommand.CommandText property is to be interpreted.</param>

''' <param name="parameters">The parameters of the Transact-SQL statement or stored procedure.</param>

''' <returns>The first column of the first row in the result set, or a null reference if the result set is empty.</returns>

Public Function ExecuteScalar(ByVal cmd As String, ByVal cmdType As CommandType, Optional ByVal parameters() As SqlParameter = Nothing) As Object

Dim connection As SqlConnection = Nothing

Dim transaction As SqlTransaction = Nothing

Dim command As SqlCommand = Nothing

Dim res As Object = Nothing

Try

connection = New SqlConnection(_connectionString)

command = New SqlCommand(cmd, connection)

command.CommandType = cmdType

Me.AssignParameters(command, parameters)

connection.Open()

transaction = connection.BeginTransaction()

command.Transaction = transaction

res = command.ExecuteScalar()

transaction.Commit()

Catch ex As Exception

If Not (transaction Is Nothing) Then

transaction.Rollback()

End If

Throw New Exception(ex.Message, ex.InnerException)

Finally

If Not (connection Is Nothing) AndAlso (connection.State = ConnectionState.Open) Then connection.Close()

If Not (command Is Nothing) Then command.Dispose()

If Not (transaction Is Nothing) Then transaction.Dispose()

End Try

Return res

End Function

''' <summary>

''' Executes the query, and returns the first column of the first row in the result set returned by the query. Additional columns or rows are ignored.

''' </summary>

''' <param name="spname">The stored procedure to execute at the data source.</param>

''' <param name="returnValue">The returned value from stored procedure.</param>

''' <param name="parameterValues">The parameter values of the stored procedure.</param>

''' <returns>The first column of the first row in the result set, or a null reference if the result set is empty.</returns>

Public Function ExecuteScalar(ByVal spname As String, ByRef returnValue As Integer, ByVal ParamArray parameterValues() As Object) As Object

Dim connection As SqlConnection = Nothing

Dim transaction As SqlTransaction = Nothing

Dim command As SqlCommand = Nothing

Dim res As Object = Nothing

Try

connection = New SqlConnection(_connectionString)

command = New SqlCommand(spname, connection)

command.CommandType = CommandType.StoredProcedure

connection.Open()

SqlCommandBuilder.DeriveParameters(command)

Me.AssignParameters(command, parameterValues)

transaction = connection.BeginTransaction()

command.Transaction = transaction

res = command.ExecuteScalar()

returnValue = command.Parameters(0).Value

transaction.Commit()

Catch ex As Exception

If Not (transaction Is Nothing) Then

transaction.Rollback()

End If

Throw New Exception(ex.Message, ex.InnerException)

Finally

If Not (connection Is Nothing) AndAlso (connection.State = ConnectionState.Open) Then connection.Close()

If Not (command Is Nothing) Then command.Dispose()

If Not (transaction Is Nothing) Then transaction.Dispose()

End Try

Return res

End Function

#End Region

#Region " ExecuteReader "

''' <summary>

''' Sends the System.Data.SqlClient.SqlCommand.CommandText to the System.Data.SqlClient.SqlCommand.Connection, and builds a System.Data.SqlClient.SqlDataReader using one of the System.Data.CommandBehavior values.

''' </summary>

''' <param name="cmd">The Transact-SQL statement or stored procedure to execute at the data source.</param>

''' <param name="cmdType">A value indicating how the System.Data.SqlClient.SqlCommand.CommandText property is to be interpreted.</param>

''' <param name="parameters">The parameters of the Transact-SQL statement or stored procedure.</param>

''' <returns>A System.Data.SqlClient.SqlDataReader object.</returns>

Public Function ExecuteReader(ByVal cmd As String, ByVal cmdType As CommandType, Optional ByVal parameters() As SqlParameter = Nothing) As IDataReader

Dim connection As SqlConnection = Nothing

Dim command As SqlCommand = Nothing

Dim res As SqlDataReader = Nothing

Try

connection = New SqlConnection(_connectionString)

command = New SqlCommand(cmd, connection)

command.CommandType = cmdType

Me.AssignParameters(command, parameters)

connection.Open()

res = command.ExecuteReader(CommandBehavior.CloseConnection)

Catch ex As Exception

Throw New Exception(ex.Message, ex.InnerException)

End Try

Return CType(res, IDataReader)

End Function

''' <summary>

''' Sends the System.Data.SqlClient.SqlCommand.CommandText to the System.Data.SqlClient.SqlCommand.Connection, and builds a System.Data.SqlClient.SqlDataReader using one of the System.Data.CommandBehavior values.

''' </summary>

''' <param name="spname">The stored procedure to execute at the data source.</param>

''' <param name="returnValue">The returned value from stored procedure.</param>

''' <param name="parameterValues">The parameter values of the stored procedure.</param>

''' <returns>A System.Data.SqlClient.SqlDataReader object.</returns>

Public Function ExecuteReader(ByVal spname As String, ByRef returnValue As Integer, ByVal ParamArray parameterValues() As Object) As IDataReader

Dim connection As SqlConnection = Nothing

Dim command As SqlCommand = Nothing

Dim res As SqlDataReader = Nothing

Try

connection = New SqlConnection(ConnectionString)

command = New SqlCommand(spname, connection)

command.CommandType = CommandType.StoredProcedure

connection.Open()

SqlCommandBuilder.DeriveParameters(command)

Me.AssignParameters(command, parameterValues)

res = command.ExecuteReader(CommandBehavior.CloseConnection)

returnValue = command.Parameters(0).Value

Catch ex As Exception

Throw New Exception(ex.Message, ex.InnerException)

End Try

Return CType(res, IDataReader)

End Function

#End Region

#Region " FillDataset "

''' <summary>

''' Adds or refreshes rows in the System.Data.DataSet to match those in the data source using the System.Data.DataSet name, and creates a System.Data.DataTable named "Table."

''' </summary>

''' <param name="cmd">The Transact-SQL statement or stored procedure to execute at the data source.</param>

''' <param name="cmdType">A value indicating how the System.Data.SqlClient.SqlCommand.CommandText property is to be interpreted.</param>

''' <param name="parameters">The parameters of the Transact-SQL statement or stored procedure.</param>

''' <returns>A System.Data.Dataset object.</returns>

Public Function FillDataset(ByVal cmd As String, ByVal cmdType As CommandType, Optional ByVal parameters() As SqlParameter = Nothing) As DataSet

Dim connection As SqlConnection = Nothing

Dim command As SqlCommand = Nothing

Dim sqlda As SqlDataAdapter = Nothing

Dim res As New DataSet

Try

connection = New SqlConnection(_connectionString)

command = New SqlCommand(cmd, connection)

command.CommandType = cmdType

AssignParameters(command, parameters)

sqlda = New SqlDataAdapter(command)

sqlda.Fill(res)

Catch ex As Exception

Throw New Exception(ex.Message, ex.InnerException)

Finally

If Not (connection Is Nothing) Then connection.Dispose()

If Not (command Is Nothing) Then command.Dispose()

If Not (sqlda Is Nothing) Then sqlda.Dispose()

End Try

Return res

End Function

#End Region

#Region " ExecuteDataset "

''' <summary>

''' Calls the respective INSERT, UPDATE, or DELETE statements for each inserted, updated, or deleted row in the System.Data.DataSet with the specified System.Data.DataTable name.

''' </summary>

''' <param name="insertCmd">A command used to insert new records into the data source.</param>

''' <param name="updateCmd">A command used to update records in the data source.</param>

''' <param name="deleteCmd">A command for deleting records from the data set.</param>

''' <param name="ds">The System.Data.DataSet to use to update the data source. </param>

''' <param name="srcTable">The name of the source table to use for table mapping.</param>

''' <returns>The number of rows successfully updated from the System.Data.DataSet.</returns>

Public Function ExecuteDataset(ByVal insertCmd As SqlCommand, ByVal updateCmd As SqlCommand, ByVal deleteCmd As SqlCommand, ByVal ds As DataSet, ByVal srcTable As String) As Integer

Dim connection As SqlConnection = Nothing

Dim sqlda As SqlDataAdapter = Nothing

Dim res As Integer = 0

Try

connection = New SqlConnection(_connectionString)

sqlda = New SqlDataAdapter

If Not (insertCmd Is Nothing) Then insertCmd.Connection = connection : sqlda.InsertCommand = insertCmd

If Not (updateCmd Is Nothing) Then updateCmd.Connection = connection : sqlda.UpdateCommand = updateCmd

If Not (deleteCmd Is Nothing) Then deleteCmd.Connection = connection : sqlda.DeleteCommand = deleteCmd

res = sqlda.Update(ds, srcTable)

Catch ex As Exception

Throw New Exception(ex.Message, ex.InnerException)

Finally

If Not (connection Is Nothing) Then connection.Dispose()

If Not (insertCmd Is Nothing) Then insertCmd.Dispose()

If Not (updateCmd Is Nothing) Then updateCmd.Dispose()

If Not (deleteCmd Is Nothing) Then deleteCmd.Dispose()

If Not (sqlda Is Nothing) Then sqlda.Dispose()

End Try

Return res

End Function

#End Region

#Region " ExecuteScript "

''' <summary>

''' Executes a SQL query file against the connection.

''' </summary>

''' <param name="filename">SQL query file name.</param>

''' <param name="parameters">The parameters of the SQL query file.</param>

Public Sub ExecuteScript(ByVal filename As String, Optional ByVal parameters() As SqlParameter = Nothing)

Dim fStream As FileStream = Nothing

Dim sReader As StreamReader = Nothing

Dim connection As SqlConnection = Nothing

Dim command As SqlCommand = Nothing

Try

fStream = New FileStream(filename, FileMode.Open, FileAccess.Read)

sReader = New StreamReader(fStream)

connection = New SqlConnection(ConnectionString)

command = connection.CreateCommand()

connection.Open()

While (Not sReader.EndOfStream)

Dim sb As New StringBuilder

While (Not sReader.EndOfStream)

Dim s As String = sReader.ReadLine

If (Not String.IsNullOrEmpty(s)) AndAlso (s.ToUpper.Trim = "GO") Then

Exit While

End If

sb.AppendLine(s)

End While

command.CommandText = sb.ToString

command.CommandType = CommandType.Text

AssignParameters(command, parameters)

command.ExecuteNonQuery()

End While

Catch ex As Exception

Throw New Exception(ex.Message, ex.InnerException)

Finally

If (Not IsNothing(connection)) AndAlso (connection.State = ConnectionState.Open) Then connection.Close()

If (Not IsNothing(command)) Then command.Dispose()

If (Not IsNothing(sReader)) Then sReader.Close()

If (Not IsNothing(fStream)) Then fStream.Close()

End Try

End Sub

#End Region

End Class

End Namespace