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Imports System.Data
Imports System.Data.SqlClient
Imports System.Configuration
Public Class clsDatabase
    Private objConn As SqlConnection
    Private objCmd As SqlCommand
    Private Trans As SqlTransaction
    Private strConnString As String

    Public Sub New()
        strConnString = System.Configuration.ConfigurationSettings.AppSettings("ConnectionString")
    End Sub

    Public Function QueryDataReader(ByVal strSQL As String) As SqlDataReader
        Dim dtReader As SqlDataReader
        objConn = New SqlConnection
        With objConn
            .ConnectionString = strConnString
            .Open()
        End With
        objCmd = New SqlCommand(strSQL, objConn)
        dtReader = objCmd.ExecuteReader()
        Return dtReader '*** Return DataReader ***'
    End Function

    Public Function QueryDataSet(ByVal strSQL As String) As DataSet
        Dim ds As New DataSet
        Dim dtAdapter As New SqlDataAdapter
        objConn = New SqlConnection
        With objConn
            .ConnectionString = strConnString
            .Open()
        End With
        objCmd = New SqlCommand
        With objCmd
            .Connection = objConn
            .CommandText = strSQL
            .CommandType = CommandType.Text
        End With
        dtAdapter.SelectCommand = objCmd
        dtAdapter.Fill(ds)
        Return ds '*** Return DataSet ***'
    End Function

    Public Function QueryDataTable(ByVal strSQL As String) As DataTable
        Dim dtAdapter As SqlDataAdapter
        Dim dt As New DataTable
        objConn = New SqlConnection
        With objConn
            .ConnectionString = strConnString
            .Open()
        End With
        dtAdapter = New SqlDataAdapter(strSQL, objConn)
        dtAdapter.Fill(dt)
        Return dt '*** Return DataTable ***'
    End Function

    Public Function QueryExecuteNonQuery(ByVal strSQL As String) As Boolean
        objConn = New SqlConnection
        With objConn
            .ConnectionString = strConnString
            .Open()
        End With
        Try
            objCmd = New SqlCommand
            With objCmd
                .Connection = objConn
                .CommandType = CommandType.Text
                .CommandText = strSQL
            End With
            objCmd.ExecuteNonQuery()
            Return True '*** Return True ***'
        Catch ex As Exception
            Return False '*** Return False ***'
        End Try
    End Function

    Public Function QueryExecuteScalar(ByVal strSQL As String) As Object
        Dim obj As Object
        objConn = New SqlConnection
        With objConn
            .ConnectionString = strConnString
            .Open()
        End With
        Try
            objCmd = New SqlCommand
            With objCmd
                .Connection = objConn
                .CommandType = CommandType.Text
                .CommandText = strSQL
            End With
            obj = objCmd.ExecuteScalar() '*** Return Scalar ***'
            Return obj
        Catch ex As Exception
            Return Nothing '*** Return Nothing ***'
        End Try
    End Function

    Public Function TransStart()
        objConn = New SqlConnection
        With objConn
            .ConnectionString = strConnString
            .Open()
        End With
        Trans = objConn.BeginTransaction(IsolationLevel.ReadCommitted)
    End Function

    Public Function TransExecute(ByVal strSQL As String) As Boolean
        objCmd = New SqlCommand
        With objCmd
            .Connection = objConn
            .Transaction = Trans
            .CommandType = CommandType.Text
            .CommandText = strSQL
        End With
        objCmd.ExecuteNonQuery()
    End Function

    Public Function TransRollBack()
        Trans.Rollback()
    End Function

    Public Function TransCommit()
        Trans.Commit()
    End Function

    Public Sub Close()
        objConn.Close()
        objConn = Nothing
    End Sub

End Class

#Region ".NET base class name space imports"
Imports System.Collections.Generic
Imports Microsoft.VisualBasic
Imports System
Imports System.Security
Imports System.Security.Permissions
Imports System.Threading
#End Region
Public Class Caragent
    Dim add_car As New addCar
    Public Function addCaragent(ByVal clsadditem As clscar) 'เพิ่มข้อมูล
        Try
            Return add_car.caradd(clsadditem)
        Catch bex As Exception
            Throw New Exception(bex.Message)
        End Try
    End Function
    Public Function carupdateagent(ByVal clsadditem As clscar) 'แก้ไข
        Try
            Return add_car.carcheck_Up(clsadditem)

        Catch bex As Exception
            Throw New Exception(bex.Message)
        End Try
    End Function
    Public Function carlistagent(ByVal clsadditem As clscar) As DataTable  'ค้นหา'
        Try
            Return add_car.carcheck_Sea(clsadditem).Tables(0)
        Catch ex As Exception
            Throw New Exception(ex.Message)
        End Try
    End Function
    Public Function carcheckagent(ByVal clsadditem As clscar) As DataTable  'เช็คID'
        Try
            Return add_car.carcheckMe(clsadditem).Tables(0)
        Catch ex As Exception
            Throw New Exception(ex.Message)
        End Try
    End Function
    Public Function cardeleteagent(ByVal clsadditem As clscar)   'ลบ'
        Try
            Return add_car.cardeletemem(clsadditem)
        Catch ex As Exception
            Throw New Exception(ex.Message)
        End Try
    End Function
End Class