求助，如何逐行读取excel表中的信息？

各位大神，请教一个问题。VB2010如何对excel进行逐行读取？


        AppXls = New Microsoft.Office.Interop.Excel.Application     '实例化Excel对象
        AppXls.Workbooks.Open(TuikaExcel)                           '打开已经存在的EXCEL文件
        AppXls.Visible = True                                       '使Excel不可见
        AppWokBook = AppXls.Workbooks(1)                        'AppWokBook对象指向工作簿"*:\*.xls"
        AppSheet = AppWokBook.Sheets(1)                          'AppSheet对象指向AppWokBook对象中的表“Sheet3”，即："*:\*.xls"中的表“Sheet3”

        index1 = IO.File.ReadAllText(indexFile, System.Text.Encoding.Default)
        x = x + index1

        Dim intlastcolnum = AppSheet.UsedRange.Columns.Count
        Dim intlastrownum = AppSheet.UsedRange.Rows.Count