Đọc và ghi file Excel bằng VB.Net

Đọc file Excel:
            Dim xlApp As Excel.Application = Nothing
            Dim xlWorkBooks As Excel.Workbooks = Nothing
            Dim xlWorkBook As Excel.Workbook = Nothing
            Dim xlWorkSheet As Excel.Worksheet = Nothing
            Dim xlWorkSheets As Excel.Sheets = Nothing
            Dim xlCells As Excel.Range = Nothing
            Dim xlRange As Excel.Range = Nothing
            xlApp = New Excel.Application
            Dim List As New List(Of List(Of Object))

            Try
                xlApp.DisplayAlerts = False
                xlWorkBooks = xlApp.Workbooks
                xlWorkBook = xlWorkBooks.Open("Đường dẫn file Excel")
                xlApp.Visible = False
                xlWorkSheets = xlWorkBook.Sheets
                xlWorkSheet = CType(xlWorkSheets("Tên Sheet"), Excel.Worksheet)
                xlRange = CType(xlWorkSheet.UsedRange.CurrentRegion, Excel.Range)

                Dim xlRow As Excel.Range = Nothing
                Dim xlCell As Excel.Range = Nothing
                For irow As Integer = 1 To xlRange.Rows.Count
                    xlRow = CType(xlRange.Rows(irow), Excel.Range)
                    Dim lstRow As New List(Of Object)
                    For icol As Integer = 1 To xlRow.Cells.Count
                        xlCell = CType(xlRange.Cells(irow, icol), Excel.Range)
                        lstRow.Add(xlCell.Value)
                    Next
                    List.Add(lstRow)
                Next
                releaseObject(xlCell)
                releaseObject(xlRow)
                releaseObject(xlRange)
                xlWorkBook.Close()
                xlApp.Quit()
                releaseObject(xlWorkSheets)
                releaseObject(xlWorkSheet)
                releaseObject(xlWorkBook)
                releaseObject(xlWorkBooks)
                releaseObject(xlApp)
            Catch
                MsgBox("Lỗi!")
            End Try


Với releaseObject được khai báo như sau:

    Public Sub releaseObject(ByVal obj As Object)
        Try
            System.Runtime.InteropServices.Marshal.FinalReleaseComObject(obj)
            obj = Nothing
        Catch ex As System.Exception
            System.Diagnostics.Debug.Print(ex.ToString())
            obj = Nothing
        Finally
            GC.Collect()
        End Try
    End Sub



********************************************
Ghi file Excel:
                    Dim oldCI As System.Globalization.CultureInfo = System.Threading.Thread.CurrentThread.CurrentCulture
                    System.Threading.Thread.CurrentThread.CurrentCulture = New System.Globalization.CultureInfo("en-US")
                    Dim xlApp As Object
                    xlApp = CreateObject("Excel.Application")
                    Dim xlWorkbook As Object = xlApp.Workbooks.Open("Đường dẫn file Excel")
                    Dim xlWorkSheet As Object = xlWorkbook.Worksheets(1)   ' 1 là thứ tự của Sheet

                    ' Set value
                    xlWorkSheet.Range("D5").Value = "Nội dung"

                    xlWorkbook.Save()
                    xlWorkbook.Close()
                    xlApp.Quit()
                    System.Threading.Thread.CurrentThread.CurrentCulture = oldCI