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