หน้า Login ครับ เหตุใดจึงขึ้น กรุณาพิมพ์ข้อมูลอย่าเดียวเลย คือ มันไม่เข้าไปตรวจสอบเงื่อนไขเลยครับ

Imports System.Data
Imports System.Data.SqlServerCe
Imports System.Data.SqlTypes
Imports System.Windows.Forms

Public Class Login
    
    Public strconnstring As String = "Data source=D:\Copy of Project New\WindowsApplication1\WindowsApplication1\Database1.sdf;"
    Public myCommand As SqlCeCommand
    Public myconnection As SqlCeConnection
    Public cmdstring As String

    Private Sub Login_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        myconnection = New SqlCeConnection(strconnstring)
        myconnection.Open()
        Try
            Dim cmdstring As String = "Select * From MyTable"
            myCommand = New SqlCeCommand(cmdstring, myconnection)
            myCommand.CommandType = CommandType.Text
            Dim myDataReader As SqlCeDataReader = myCommand.ExecuteReader()

        Catch ex As Exception
            MsgBox(ex.Message)

        End Try


    End Sub

    Private Sub OK_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles OK.Click
        Try
            cmdstring = "Select password FROM [myTable] where ID=" & txtid.Text
            myCommand = New SqlCeCommand(cmdstring, myconnection)
            myCommand.CommandType = CommandType.Text
            Dim myDataReader As SqlCeDataReader = myCommand.ExecuteReader()
            Dim strPassword As String


            If myDataReader.HasRows Then
                myDataReader.Read()
                If IsDBNull(myDataReader("password")) Then
                    strPassword = ""
                Else
                    strPassword = Trim(myDataReader("password"))
                End If
                If strPassword <> Trim(txtpass.Text) Then
                    MsgBox("Password mismatch")
                Else
                    MsgBox("ล็อคอินเรียบร้อย")
                    Me.Hide()
                    Computer.Show()


                End If
            Else
                MsgBox("ไม่มีข้อมูลในระบบ")

            End If

        Catch ex As Exception
            MsgBox("กรุณาพิมพ์ข้อมูล")

        End Try

    End Sub