VB.NET ดู โค้ด Update ให้หน่อยครับ แก้ไม่ได้สักที ช่วยแก้ให้หน่อยนะครับ

Imports System.Data
Imports System.Data.OleDb
Partial Class Product
    Inherits System.Web.UI.Page
    Dim mycon As OleDbConnection
    Dim myAdapter As OleDbDataAdapter
    Dim dataset As New DataSet
    Dim mycmd As OleDbCommand
    Dim intId As Integer
    Dim myreader As OleDbDataReader
    Dim myupdate As String

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        mycon = New OleDbConnection("PROVIDER=Microsoft.Jet.OLEDB.4.0;Data Source=d:\inventory.mdb")
    End Sub

    Protected Sub Button3_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnsave.Click
        mycmd = New OleDbCommand("Insert INTO customer(ID,cusname,cusAddress,cusIdentification,type,Tel) values (txtId.text,txtName.text,txtAdd.text,txtIden.text," & type.SelectedValue & ",txtTelephone.text)", mycon)


        mycmd.Parameters.AddWithValue("@ID", txtId.Text)
        mycmd.Parameters.AddWithValue("@cusname", txtName.Text)
        mycmd.Parameters.AddWithValue("@cusAddress", txtAdd.Text)
        mycmd.Parameters.AddWithValue("@cusIdentification", txtIden.Text)

        If Type.SelectedValue = "Premiem" Then
            mycmd.Parameters.AddWithValue("@type", Type.SelectedValue)
        ElseIf Type.SelectedValue = "Silver" Then
            mycmd.Parameters.AddWithValue("@type", Type.SelectedValue)
        Else
            mycmd.Parameters.AddWithValue("@type", Type.SelectedValue)
        End If
        mycmd.Parameters.AddWithValue("@Tel", txtTelephone.Text)

        mycon.Open()
        mycmd.ExecuteNonQuery()
        mycon.Close()

        txtkey.Text = ""
        txtId.Text = ""
        txtName.Text = ""
        txtAdd.Text = ""
        txtIden.Text = ""
        txtTelephone.Text = ""
    End Sub

    Protected Sub Button8_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnadd.Click
        mycon.Open()
        mycmd = New OleDbCommand("select* from Customer", mycon)
        Dim dataRead As OleDbDataReader = mycmd.ExecuteReader
        While dataRead.Read()
            intId = (dataRead("ID"))
        End While
        mycon.Close()
        txtId.Text = intId + 1
        txtName.Focus()

    End Sub

    Protected Sub Button5_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btndel.Click
        mycmd = New OleDbCommand("DELETE FROM Customer WHERE ID = " & txtId.Text, mycon)
        mycon.Open()
        mycmd.ExecuteNonQuery()
        mycon.Close()
        txtId.Text = ""
        txtName.Text = ""
        txtAdd.Text = ""
        txtIden.Text = ""
        type.Text = ""
        txtTelephone.Text = ""

    End Sub

    Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnsearch.Click
        mycon.Open()
        If rbid.Checked Then
            mycmd = New OleDbCommand("SELECT * FROM Customer WHERE ID = @ID", mycon)
            mycmd.Parameters.AddWithValue("@ID", txtkey.Text)
            myreader = mycmd.ExecuteReader()
            While myreader.Read()
                txtId.Text = CStr(myreader.Item("id"))
                txtName.Text = CStr(myreader.Item("cusname"))
                txtAdd.Text = CStr(myreader.Item("cusaddress"))
                txtIden.Text = CStr(myreader.Item("cusidentification"))
                type.Text = CStr(myreader.Item("type"))
                txtTelephone.Text = CStr(myreader.Item("Tel"))
            End While
        End If
        If rbname.Checked Then

            mycmd = New OleDbCommand("SELECT * FROM Customer WHERE cusname = @cusname", mycon)
            mycmd.Parameters.AddWithValue("@cusname", txtkey.Text)
            myreader = mycmd.ExecuteReader()
            While myreader.Read()
                txtId.Text = CStr(myreader.Item("id"))
                txtName.Text = CStr(myreader.Item("cusname"))
                txtAdd.Text = CStr(myreader.Item("cusaddress"))
                txtIden.Text = CStr(myreader.Item("cusidentification"))
                type.Text = CStr(myreader.Item("type"))
                txtTelephone.Text = CStr(myreader.Item("Tel"))
            End While
        End If

        If rbiden.Checked Then

            mycmd = New OleDbCommand("SELECT * FROM Customer WHERE cusIdentification = @cusIdentification", mycon)
            mycmd.Parameters.AddWithValue("@ID", txtkey.Text)
            myreader = mycmd.ExecuteReader()
            While myreader.Read()
                txtId.Text = CStr(myreader.Item("id"))
                txtName.Text = CStr(myreader.Item("cusname"))
                txtAdd.Text = CStr(myreader.Item("cusaddress"))
                txtIden.Text = CStr(myreader.Item("cusidentification"))
                type.Text = CStr(myreader.Item("type"))
                txtTelephone.Text = CStr(myreader.Item("Tel"))
            End While

        End If
        myreader.Close()
        mycon.Close()
    End Sub

    Protected Sub Button2_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnclear.Click
        txtkey.Text = ""
        txtId.Text = ""
        txtName.Text = ""
        txtAdd.Text = ""
        txtIden.Text = ""
        txtTelephone.Text = ""
        rbid.Checked = False
        rbname.Checked = False
        rbiden.Checked = False
        type.Visible = True
    End Sub

    Protected Sub Button4_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnupdate.Click
        myupdate = "update customer set cusname = @cusname,cusAddress = @cusAddress,cusidentification = @cusidentification,type = @type,Tel = @Tel where ID=" & txtId.Text & " "
        mycmd = New OleDbCommand(myupdate, mycon)
        mycmd.Parameters.AddWithValue("@cusname", txtName.Text)
        mycmd.Parameters.AddWithValue("@Address", txtAdd.Text)
        mycmd.Parameters.AddWithValue("@cusIdentification", txtIden.Text)
        mycmd.Parameters.AddWithValue("@type", type.Text)
        If type.SelectedValue = "Premiem" Then
            mycmd.Parameters.AddWithValue("@type", type.SelectedValue)
        ElseIf type.SelectedValue = "Silver" Then
            mycmd.Parameters.AddWithValue("@type", type.SelectedValue)
        Else
            mycmd.Parameters.AddWithValue("@type", type.SelectedValue)
        End If
        mycmd.Parameters.AddWithValue("@Tel", txtTelephone.Text)

        mycon.Open()
        mycmd.ExecuteNonQuery()
        mycon.Close()
        txtkey.Text = ""
        txtId.Text = ""
        txtName.Text = ""
        txtAdd.Text = ""
        txtIden.Text = ""
        txtTelephone.Text = ""

    End Sub
End Class