Simple reading of EXCEL

Imports ExcelPublic Class ExcelMgr2    Private _app As ApplicationClass    Private _workBook As Workbook    Private _currentSheet As Worksheet#Region " Property "    Public Property CurrentSheet() As Worksheet        Get            Return _currentSheet        End Get        Set(ByVal value As Worksheet)            If value Is Nothing Then                Return            End If            _currentSheet = value        End Set    End Property#End Region#Region " Method "    Public Sub New(ByVal FileName As String)        Open(FileName)    End Sub    Private Sub Open(ByVal FileName As String)        _app = New ApplicationClass()        _workBook = _app.Workbooks.Open(FileName)        _currentSheet = CType(_workBook.Worksheets(1), Worksheet)    End Sub    Public Function GetCellValue(ByVal SheetNo As Integer, ByVal RowNo As Integer, ByVal ColNo As Integer) _        As String        Dim sheet As Worksheet        Dim value As String        If SheetNo <= 0 OrElse SheetNo > _workBook.Worksheets.Count Then            Throw New ExcelException(ExcelException.ERR_NUM_SHEET1)        End If        value = ""        sheet = CType(_workBook.Worksheets(SheetNo), Worksheet)        value = GetCellValue(sheet, RowNo, ColNo)        Return value    End Function    Public Function GetCellValue(ByVal SheetName As String, ByVal RowNo As Integer, ByVal ColNo As Integer) _        As String        Dim sheet As Worksheet        Dim value As String        sheet = Nothing        value = ""        For Each s As Worksheet In _workBook.Worksheets            If Equals(s.Name, SheetName) = True Then                sheet = s                Exit For            End If        Next s        If sheet Is Nothing Then            Throw New ExcelException(ExcelException.ERR_NUM_SHEET1)        End If        value = GetCellValue(sheet, RowNo, ColNo)        Return value    End Function    Public Function GetCellValue(ByVal sheet As Worksheet, ByVal RowNo As Integer, ByVal ColNo As Integer) _        As String        Dim cell As Range        Dim value As String        cell = CType(sheet.Cells.Item(RowNo, ColNo), Range)        value = CStr(cell.Value)        If value Is Nothing Then            value = ""        End If        Return value    End Function    Public Function GetCellValue(ByVal RowNo As Integer, ByVal ColNo As Integer) As String        Dim value As String        value = GetCellValue(_currentSheet, RowNo, ColNo)        Return value    End Function    Public Sub Close()        If _workBook IsNot Nothing Then            _workBook.Close()        End If        If _app IsNot Nothing Then            _app.Quit()        End If        _workBook = Nothing        _app = Nothing        GC.Collect()    End Sub#End RegionEnd Class

 

 

Public Class ExcelException    Inherits Exception    Public Const ERR_NUM_SHEET1 As Integer = -8800301        'sheet not exist    Public Const ERR_NUM_CELL1 As Integer = -8800501    Private _errNumber As Integer    Private _ex As Exception    Public Sub New(ByVal Message As String)        _ex = New Exception(Message)    End Sub    Public Sub New(ByVal ErrorNumber As Integer)        _errNumber = ErrorNumber        Select Case _errNumber            Case ERR_NUM_SHEET1                _ex = New Exception(Message)            Case ERR_NUM_CELL1                _ex = New Exception(Message)        End Select    End Sub    Public Sub New(ByVal ErrorNumber As Integer, ByVal Message As String)        _errNumber = ErrorNumber        _ex = New Exception(Message)    End Sub    Public Sub New(ByVal Message As String, ByVal ex As Exception)        _ex = New Exception(Message, ex)    End Sub    Public Sub New(ByVal ErrorNumber As Integer, ByVal ex As Exception)        _errNumber = ErrorNumber        _ex = New Exception(Message, ex)    End Sub    Public ReadOnly Property Number() As Integer        Get            Return _errNumber        End Get    End Property    Public Overrides ReadOnly Property Message() As String        Get            If _ex IsNot Nothing Then                Return _ex.Message            Else                Return ""            End If        End Get    End PropertyEnd Class