How to read excel file and display in grid using asp.net

Please upload the Excel document:<asp:FileUpload ID="FileUpload1" runat="server" />
        <asp:Button ID="btnSave" runat="server" Text="Save" />
    <br />
    <asp:GridView ID="GridView1" runat="server">
    </asp:GridView>

Protected Sub btnSave_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnSave.Click
        If FileUpload1.HasFile Then
            Dim FileName As String = Path.GetFileName(FileUpload1.PostedFile.FileName)
            Dim Extension As String = Path.GetExtension(FileUpload1.PostedFile.FileName)
            Dim FolderPath As String = ConfigurationManager.AppSettings("FolderPath")

            Dim FilePath As String = Server.MapPath(FolderPath & "\" & FileName)
            FileUpload1.SaveAs(FilePath)
            Import_To_Grid(FilePath, Extension)
        End If
    End Sub

Private Sub Import_To_Grid(ByVal FilePath As String, ByVal Extension As String)
        Dim conStr As String = ""
        Select Case Extension
            Case ".xls"
                'Excel 97-03
                conStr = ConfigurationManager.ConnectionStrings("Excel03ConString").ConnectionString()
                Exit Select
            Case ".xlsx"
                'Excel 07
                conStr = ConfigurationManager.ConnectionStrings("Excel07ConString").ConnectionString()
                Exit Select
        End Select

        conStr = String.Format(conStr, FilePath)

        Dim connExcel As New OleDbConnection(conStr)
        Dim cmdExcel As New OleDbCommand()
        Dim oda As New OleDbDataAdapter()
        Dim dt As New DataTable()

        cmdExcel.Connection = connExcel

        'Get the name of First Sheet
        connExcel.Open()
        Dim dtExcelSchema As DataTable
        dtExcelSchema = connExcel.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, Nothing)
        Dim SheetName As String = dtExcelSchema.Rows(0)("TABLE_NAME").ToString()
        connExcel.Close()

        'Read Data from First Sheet
        connExcel.Open()
        cmdExcel.CommandText = "SELECT * From [" & SheetName & "]"
        oda.SelectCommand = cmdExcel
        oda.Fill(dt)
        connExcel.Close()

        'Bind Data to GridView

        GridView1.Caption = Path.GetFileName(FilePath)
        GridView1.DataSource = dt
        GridView1.DataBind()
        CreateTextboxGridview()
    End Sub

Imports System.Data.Sql
Imports System.Data.SqlClient
Imports System.Data
Imports System.Data.OleDb
Imports System.IO